Skip to main content

burn_tensor/tensor/api/
base.rs

1#![allow(clippy::single_range_in_vec_init)]
2use crate::backend::ExecutionError;
3use crate::check::unwrap_shape_reshape;
4
5use burn_backend::Scalar;
6pub use burn_backend::tensor::BasicOps;
7
8use alloc::vec::Vec;
9
10use alloc::format;
11use alloc::string::String;
12use alloc::vec;
13
14use burn_std::stub::RwLock;
15use core::iter::repeat;
16use core::{fmt::Debug, ops::Range};
17use serde::{Deserialize, Deserializer};
18
19use crate::{AsIndex, Slice, SliceArg, wrap_index};
20use crate::{
21    Bool, ElementConversion, Float, Int, Shape, TensorData, TensorKind, TensorMetadata,
22    backend::Backend, check,
23};
24use crate::{DType, Element};
25use crate::{IndexingUpdateOp, TensorCreationOptions};
26use crate::{cast::ToElement, check::TensorCheck};
27use serde::{Serialize, Serializer};
28
29/// A tensor with a given backend, shape and data type.
30///
31/// # Indexing
32/// Indexing a tensor can be done using [`slice`](Tensor::slice) for all tensor types
33/// or [`select`](Tensor::select) for numeric types.
34///
35/// ## Example
36///
37/// ```rust
38/// use burn_tensor::backend::Backend;
39/// use burn_tensor::Tensor;
40/// use burn_tensor::Int;
41///
42/// fn example<B: Backend>() {
43///     let device = Default::default();
44///
45///     let tensor = Tensor::<B, 2>::from_data(
46///         [
47///             [3.0, 4.9, 2.0],
48///             [2.0, 1.9, 3.0],
49///             [6.0, 1.5, 7.0],
50///             [3.0, 4.9, 9.0],
51///         ],
52///         &device,
53///     );
54///
55///     // Slice the tensor to get the second and third rows:
56///     // [[2.0, 1.9, 3.0], [6.0, 1.5, 7.0]]
57///     // The resulting tensor will have dimensions [2, 3].
58///     let slice = tensor.clone().slice([1..3]);
59///     println!("{slice}");
60///
61///     // Slice the tensor to get the first two rows and the first 2 columns:
62///     // [[3.0, 4.9], [2.0, 1.9]]
63///     // The resulting tensor will have dimensions [2, 2].
64///     let slice = tensor.clone().slice([0..2, 0..2]);
65///     println!("{slice}");
66///
67///     // Index the tensor along the dimension 1 to get the elements 0 and 2:
68///     // [[3.0, 2.0], [2.0, 3.0], [6.0, 7.0], [3.0, 9.0]]
69///     // The resulting tensor will have dimensions [4, 2]
70///     let indices = Tensor::<B, 1, Int>::from_data([0, 2], &device);
71///     let indexed = tensor.select(1, indices);
72///     println!("{indexed}");
73/// }
74/// ```
75#[derive(new, Clone, Debug)]
76pub struct Tensor<B, const D: usize, K = Float>
77where
78    B: Backend,
79    K: TensorKind<B>,
80{
81    pub(crate) primitive: K::Primitive,
82}
83
84impl<B, const D: usize, K, T> From<T> for Tensor<B, D, K>
85where
86    B: Backend,
87    K: BasicOps<B>,
88    T: Into<TensorData>,
89{
90    fn from(value: T) -> Self {
91        Tensor::from_data(value.into(), &Default::default())
92    }
93}
94
95impl<B, const D: usize, K> Tensor<B, D, K>
96where
97    B: Backend,
98    K: BasicOps<B>,
99    K::Elem: Element,
100{
101    /// Executes an operation on the tensor and modifies its value.
102    ///
103    /// # Notes
104    ///
105    /// This won't necessarily reuse the same tensor data/buffer, but it should if there is
106    /// no other reference pointing to the same tensor.
107    ///
108    /// Wrapping operations with inplace is not an optimization, it's mainly there if you
109    /// want to mutate a tensor by using owned operations. A plausible usage would be to
110    /// update the weights of a mutable model reference.
111    pub fn inplace<F: FnOnce(Self) -> Self>(&mut self, func: F) {
112        let mut tensor_owned = Tensor::empty([0; D], &self.device());
113        core::mem::swap(&mut tensor_owned, self);
114
115        let mut tensor_new = func(tensor_owned);
116        core::mem::swap(&mut tensor_new, self);
117    }
118
119    /// Converts the tensor into a primitive tensor.
120    pub fn into_primitive(self) -> K::Primitive {
121        self.primitive
122    }
123
124    /// Converts from a primitive tensor into a tensor.
125    pub fn from_primitive(tensor: K::Primitive) -> Self {
126        Self::new(tensor)
127    }
128
129    /// Returns the number of dimensions of the tensor.
130    pub fn rank(&self) -> usize {
131        self.primitive.rank()
132    }
133
134    /// Returns the tensor primitive data type.
135    ///
136    /// # Note
137    /// Some element types are encoded in different primitive types depending on the backend
138    /// (e.g., bool could be encoded as `u8` or `u32`).
139    pub fn dtype(&self) -> DType {
140        self.primitive.dtype()
141    }
142
143    /// Create an empty tensor of the given shape.
144    ///
145    /// # Arguments
146    ///
147    /// - `shape`: The shape of the tensor.
148    /// - `device`: The device where the tensor will be created.
149    ///
150    /// # Example
151    /// ```rust
152    /// use burn_tensor::backend::Backend;
153    /// use burn_tensor::Tensor;
154    ///
155    /// fn example<B: Backend>() {
156    ///    let device = Default::default();
157    ///    // Create an empty tensor with dimensions [2, 3, 4].
158    ///    let tensor = Tensor::<B, 3>::empty([2, 3, 4], &device);
159    /// }
160    /// ```
161    pub fn empty<S: Into<Shape>>(shape: S, options: impl Into<TensorCreationOptions<B>>) -> Self {
162        let opt = options.into();
163        let shape = shape.into();
164        let dtype = opt.resolve_policy(K::Elem::dtype());
165        check!(TensorCheck::creation_ops::<D>("Empty", &shape.dims));
166        Self::new(K::empty(shape, &opt.device, dtype))
167    }
168
169    /// Create a tensor of the given shape where each element is zero.
170    ///
171    /// # Example
172    ///
173    /// ```rust
174    /// use burn_tensor::backend::Backend;
175    /// use burn_tensor::{Tensor, Shape};
176    ///
177    /// fn example<B: Backend>() {
178    ///    let device = B::Device::default();
179    ///    let tensor = Tensor::<B, 2>::zeros(Shape::new([2, 3]), &device);
180    ///    println!("{tensor}");
181    ///    // [[0.0, 0.0, 0.0], [0.0, 0.0, 0.0]]
182    /// }
183    /// ```
184    pub fn zeros<S: Into<Shape>>(shape: S, options: impl Into<TensorCreationOptions<B>>) -> Self {
185        let opt = options.into();
186        let shape = shape.into();
187        let dtype = opt.resolve_policy(K::Elem::dtype());
188        check!(TensorCheck::creation_ops::<D>("Zeros", &shape.dims));
189        Self::new(K::zeros(shape, &opt.device, dtype))
190    }
191
192    /// Returns a new tensor with the same shape, dtype, and device as the current tensor filled with zeros.
193    ///
194    /// # Example
195    ///
196    /// ```rust
197    /// use burn_tensor::backend::Backend;
198    /// use burn_tensor::{Tensor, Shape};
199    ///
200    /// fn example<B: Backend>() {
201    ///   let device = B::Device::default();
202    ///   let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
203    ///   let tensor = tensor.zeros_like();
204    ///   println!("{tensor}");
205    ///   // [[0.0, 0.0, 0.0], [0.0, 0.0, 0.0]]
206    /// }
207    /// ```
208    pub fn zeros_like(&self) -> Self {
209        Self::new(K::zeros(self.shape(), &self.device(), self.dtype()))
210    }
211
212    /// Create a tensor of the given shape where each element is one.
213    ///
214    /// # Example
215    ///
216    /// ```rust
217    /// use burn_tensor::backend::Backend;
218    /// use burn_tensor::{Tensor, Shape};
219    ///
220    /// fn example<B: Backend>() {
221    ///   let device = B::Device::default();
222    ///   let tensor = Tensor::<B, 2>::ones(Shape::new([2, 3]), &device);
223    ///   println!("{tensor}");
224    ///   // [[1.0, 1.0, 1.0], [1.0, 1.0, 1.0]]
225    /// }
226    /// ```
227    pub fn ones<S: Into<Shape>>(shape: S, options: impl Into<TensorCreationOptions<B>>) -> Self {
228        let opt = options.into();
229        let shape = shape.into();
230        let dtype = opt.resolve_policy(K::Elem::dtype());
231        check!(TensorCheck::creation_ops::<D>("Ones", &shape.dims));
232        Self::new(K::ones(shape, &opt.device, dtype))
233    }
234
235    /// Returns a new tensor with the same shape, dtype, and device as the current tensor filled with ones.
236    ///
237    /// # Example
238    ///
239    /// ```rust
240    /// use burn_tensor::backend::Backend;
241    /// use burn_tensor::{Tensor, Shape};
242    ///
243    /// fn example<B: Backend>() {
244    ///    let device = B::Device::default();
245    ///    let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
246    ///    let tensor = tensor.ones_like();
247    ///    println!("{tensor}");
248    ///    // [[1.0, 1.0, 1.0], [1.0, 1.0, 1.0]]
249    /// }
250    /// ```
251    pub fn ones_like(&self) -> Self {
252        Self::new(K::ones(self.shape(), &self.device(), self.dtype()))
253    }
254
255    /// Create a tensor of the given shape where each element is equal to the provided value.
256    ///
257    /// # Example
258    ///
259    /// ```rust
260    /// use burn_tensor::backend::Backend;
261    /// use burn_tensor::{Tensor, Shape};
262    ///
263    /// fn example<B: Backend>() {
264    ///   let device = B::Device::default();
265    ///   let tensor = Tensor::<B, 2>::full(Shape::new([2, 3]), 5.0, &device);
266    ///   println!("{tensor}");
267    ///   // [[5.0, 5.0, 5.0], [5.0, 5.0, 5.0]]
268    /// }
269    /// ```
270    pub fn full<S: Into<Shape>, E: ElementConversion>(
271        shape: S,
272        fill_value: E,
273        options: impl Into<TensorCreationOptions<B>>,
274    ) -> Self {
275        let opt = options.into();
276        let shape = shape.into();
277        let dtype = opt.resolve_policy(K::Elem::dtype());
278        check!(TensorCheck::creation_ops::<D>("Full", &shape.dims));
279        Self::new(K::full(
280            shape,
281            Scalar::new(fill_value, &dtype),
282            &opt.device,
283            dtype,
284        ))
285    }
286
287    /// Returns a new tensor with the same shape, dtype, and device as the current tensor,
288    /// filled with the provided value.
289    ///
290    /// # Example
291    ///
292    /// ```rust
293    /// use burn_tensor::backend::Backend;
294    /// use burn_tensor::{Tensor, Shape};
295    ///
296    /// fn example<B: Backend>() {
297    ///    let device = B::Device::default();
298    ///    let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
299    ///    let tensor = tensor.full_like(5.0);
300    ///    println!("{tensor}");
301    ///    // [[5.0, 5.0, 5.0], [5.0, 5.0, 5.0]]
302    /// }
303    /// ```
304    pub fn full_like<E: ElementConversion>(&self, fill_value: E) -> Self {
305        let dtype = self.dtype();
306        Self::new(K::full(
307            self.shape(),
308            Scalar::new(fill_value, &dtype),
309            &self.device(),
310            dtype,
311        ))
312    }
313
314    /// Returns the dimensions of the current tensor.
315    ///
316    /// # Example
317    /// ```rust
318    /// use burn_tensor::backend::Backend;
319    /// use burn_tensor::Tensor;
320    ///
321    /// fn example<B: Backend>() {
322    ///   let device = Default::default();
323    ///   let tensor = Tensor::<B, 3>::ones([2, 3, 4], &device);
324    ///   let dims = tensor.dims(); // [2, 3, 4]
325    ///   println!("{dims:?}");
326    /// }
327    /// ```
328    pub fn dims(&self) -> [usize; D] {
329        Self::shape(self).dims()
330    }
331
332    /// Returns the shape of the current tensor.
333    ///
334    /// # Example
335    /// ```rust
336    /// use burn_tensor::backend::Backend;
337    /// use burn_tensor::Tensor;
338    ///
339    /// fn example<B: Backend>() {
340    ///    let device = Default::default();
341    ///    let tensor = Tensor::<B, 3>::ones([2, 3, 4], &device);
342    ///    // Shape { dims: [2, 3, 4] }
343    ///    let shape = tensor.shape();
344    /// }
345    /// ```
346    pub fn shape(&self) -> Shape {
347        self.primitive.shape()
348    }
349
350    /// Reshape the tensor to have the given shape.
351    ///
352    /// The tensor has the same data and number of elements as the input.
353    ///
354    /// A `-1` in the shape is used to infer the remaining dimensions, e.g.: `[2, -1]`
355    /// will reshape the tensor with [2, 3, 4] dimensions to [2, 12].
356    ///
357    /// A `0` in the shape instructs to keep the current dimension from the original tensor,
358    /// e.g.: `[2, 0, 4]` will reshape the tensor with [2, 3, 4] dimensions to [2, 3, 4].
359    /// This is useful when reshaping tensors with unknown dimensions and combining with `-1`
360    /// to infer the remaining dimensions, e.g. `[0, -1]` will reshape the tensor
361    /// with [1, 3, 4] dimensions to [1, 12].
362    ///
363    /// # Arguments
364    /// - `shape`: The new shape of the tensor.
365    ///
366    /// # Panics
367    /// - If the tensor contains more than one `-1` in the shape.
368    /// - If the tensor contains values that are not positive (other than -1).
369    /// - If the shape does not match the number of elements of the original shape.
370    ///
371    /// # Example
372    ///
373    /// ```rust
374    /// use burn_tensor::backend::Backend;
375    /// use burn_tensor::Tensor;
376    ///
377    /// fn example<B: Backend>() {
378    ///    let device = Default::default();
379    ///    // Create a tensor with dimensions [2, 3, 4]
380    ///    let tensor = Tensor::<B, 3>::ones([2, 3, 4], &device);
381    ///    // Reshape it to [2, 12], where 12 is inferred from the number of elements.
382    ///    let reshaped = tensor.reshape([2, -1]);
383    ///    println!("{reshaped}");
384    /// }
385    /// ```
386    pub fn reshape<const D2: usize, S: ReshapeArgs<D2>>(self, shape: S) -> Tensor<B, D2, K> {
387        // Convert reshape args to shape
388        let shape = shape.into_shape::<D2>(self.shape());
389        Tensor::new(K::reshape(self.primitive, shape))
390    }
391
392    /// Transpose the tensor.
393    ///
394    /// For a 2D tensor, this is the standard matrix transpose. For `D > 2`, the transpose is
395    /// applied on the last two dimensions. For example, the transpose of a tensor with shape
396    /// `[1, 2, 3, 4]` will have shape `[1, 2, 4, 3]`.
397    ///
398    /// See also [`permute`](Tensor::permute).
399    ///
400    /// # Arguments
401    ///
402    /// * `tensor` - The tensor to transpose.
403    ///
404    /// # Returns
405    ///
406    /// The transposed tensor.
407    ///
408    /// # Example
409    ///
410    /// ```rust
411    /// use burn_tensor::backend::Backend;
412    /// use burn_tensor::Tensor;
413    ///
414    /// fn example<B: Backend>() {
415    ///     let device = Default::default();
416    ///     // Create a 2D tensor of shape [2, 3]
417    ///     let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
418    ///
419    ///     // Transpose the tensor:
420    ///     // [[1.0, 5.0], [-2.0, 9.0], [3.0, 6.0]]
421    ///     // The resulting tensor will have dimensions [3, 2].
422    ///     let transposed = tensor.transpose();
423    ///     println!("{transposed}");
424    /// }
425    /// ```
426    pub fn transpose(self) -> Tensor<B, D, K> {
427        Tensor::new(K::transpose(self.primitive))
428    }
429
430    /// Alias for `transpose`.
431    #[inline(always)]
432    pub fn t(self) -> Tensor<B, D, K> {
433        self.transpose()
434    }
435
436    /// Swaps two dimensions of a tensor.
437    ///
438    /// This is a no-op when `dim1 == dim2`, assuming both are within bounds.
439    ///
440    /// # Arguments
441    ///
442    /// * `tensor` - The tensor to swap the dimensions of.
443    /// * `dim1` - The first dimension to swap, supports negative indexing.
444    /// * `dim2` - The second dimension to swap, supports negative indexing.
445    ///
446    /// # Returns
447    ///
448    /// The tensor with the dimensions swapped.
449    ///
450    /// # Panics
451    ///
452    /// When dimensions are out of bounds.
453    ///
454    /// # Example
455    ///
456    /// ```rust
457    /// use burn_tensor::backend::Backend;
458    /// use burn_tensor::Tensor;
459    ///
460    /// fn example<B: Backend>() {
461    ///     let device = Default::default();
462    ///     // Create a 2D tensor of shape [2, 3]
463    ///     let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
464    ///
465    ///     // Swap the dimensions 0 and -1 (equivalent to `tensor.transpose()`):
466    ///     // [[1.0, 5.0], [-2.0, 9.0], [3.0, 6.0]]
467    ///     // The resulting tensor will have dimensions [3, 2].
468    ///     let swapped = tensor.swap_dims(0, -1);
469    ///     println!("{swapped}");
470    /// }
471    /// ```
472    pub fn swap_dims<Dim1, Dim2>(self, dim1: Dim1, dim2: Dim2) -> Tensor<B, D, K>
473    where
474        Dim1: AsIndex,
475        Dim2: AsIndex,
476    {
477        let dim1 = dim1.expect_dim_index(D);
478        let dim2 = dim2.expect_dim_index(D);
479        check!(TensorCheck::swap_dims::<D>(dim1, dim2));
480        if dim1 == dim2 {
481            self
482        } else {
483            Tensor::new(K::swap_dims(self.primitive, dim1, dim2))
484        }
485    }
486
487    /// Permute the dimensions of the tensor.
488    ///
489    /// This is a no-op when the resolved `axes` match the current order.
490    ///
491    /// # Arguments
492    ///
493    /// * `axes` - The new order of the dimensions. The length of the axes
494    ///   must be equal to the number of dimensions of the tensor.
495    ///   The values must be unique and in the range of the number of dimensions.
496    ///   The values can be negative, in which case they are used as an offset from the end.
497    ///
498    /// # Returns
499    ///
500    /// The tensor with the dimensions permuted.
501    ///
502    /// # Example
503    ///
504    /// ```rust
505    /// use burn_tensor::backend::Backend;
506    /// use burn_tensor::Tensor;
507    ///
508    /// fn example<B: Backend>() {
509    ///     let device = Default::default();
510    ///     // Create a 2D tensor of shape [3, 2]
511    ///     let tensor = Tensor::<B, 2>::from_data([[1.0, 5.0], [-2.0, 9.0], [3.0, 6.0]], &device);
512    ///
513    ///     // Permute the dimensions 1 and 0:
514    ///     // [[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]]
515    ///     // The resulting tensor will have dimensions [3, 2].
516    ///     let permuted = tensor.permute([1, 0]);
517    ///     println!("{permuted}");
518    /// }
519    /// ```
520    pub fn permute<Dim>(self, axes: [Dim; D]) -> Tensor<B, D, K>
521    where
522        Dim: AsIndex,
523    {
524        let mut no_op = true;
525        let mut fixed_axes = [0; D];
526        for (i, axis) in axes.into_iter().enumerate() {
527            let dim = axis.expect_dim_index(D);
528            no_op &= dim == i;
529            fixed_axes[i] = dim;
530        }
531
532        if no_op {
533            self
534        } else {
535            check!(TensorCheck::permute(fixed_axes));
536            Tensor::new(K::permute(self.primitive, &fixed_axes))
537        }
538    }
539
540    /// Moves the dimension(s) of input at the position(s) in source to the position(s) in destination.
541    ///
542    /// Other dimensions of input that are not explicitly moved remain in their original order and appear
543    /// at the positions not specified in destination.
544    ///
545    /// # Arguments
546    ///
547    /// * `src` - The dimension(s) to move. The values must be unique and in the range of the number of dimensions.
548    ///   The values can be negative, in which case they are used as an offset from the end.
549    ///
550    /// * `dst` - Destination positions for each of the original dims. These must also be unique.
551    ///
552    /// # Panics
553    ///
554    /// - If the source and destination dimensions are not of the same length.
555    /// - If the source and destination vectors contain duplicate values.
556    /// - If the source and destination vectors contain values that are out of bounds.
557    ///
558    /// # Returns
559    ///
560    /// The tensor with the dimensions moved.
561    ///
562    /// # Example
563    ///
564    /// ```rust
565    /// use burn_tensor::backend::Backend;
566    /// use burn_tensor::Tensor;
567    ///
568    /// fn example<B: Backend>() {
569    ///     let device = Default::default();
570    ///     // Create a 3D tensor of shape [3, 2, 1]
571    ///     let tensor = Tensor::<B, 3>::from_data([[[1.0], [5.0]], [[-2.0], [9.0]], [[3.0], [6.0]]], &device);
572    ///
573    ///     // Move the dimensions 0 and 1:
574    ///     // [[[1.0], [-2.0], [3.0]], [[5.0], [9.0], [6.0]]]
575    ///     // The resulting tensor will have dimensions [2, 3, 1].
576    ///     let moved = tensor.movedim(1, 0);
577    ///     println!("{moved}");
578    /// }
579    /// ```
580    ///
581    /// # Note
582    ///
583    /// This is a syntactic sugar for `permute`. It is used widely enough, so we define a separate Op
584    /// for it
585    pub fn movedim<S1: MovedimArgs, S2: MovedimArgs>(self, src: S1, dst: S2) -> Tensor<B, D, K> {
586        let source_dims = src.into_dim_vec::<D>();
587        let destination_dims = dst.into_dim_vec::<D>();
588
589        check!(TensorCheck::movedim_args_length(
590            &source_dims,
591            &destination_dims
592        ));
593
594        let mut m = [-1; D];
595        for (&d, &s) in destination_dims.iter().zip(source_dims.iter()) {
596            m[d] = s as isize;
597        }
598        let mut axes: [isize; D] = [0; D];
599        let mut source_i = 0;
600        for (dest_i, item) in axes.iter_mut().enumerate().take(D) {
601            *item = if m[dest_i] != -1 {
602                m[dest_i]
603            } else {
604                while source_dims.contains(&source_i) {
605                    source_i += 1;
606                }
607                let result = source_i as isize;
608                source_i += 1;
609                result
610            };
611        }
612
613        self.permute(axes)
614    }
615
616    /// Reverse the order of elements in the tensor along the given dimensions.
617    ///
618    /// # Arguments
619    ///
620    /// * `axes` - The dimensions to reverse. The values must be unique and in the range of the number of dimensions.
621    ///   The values can be negative, in which case they are used as an offset from the end.
622    ///
623    /// # Returns
624    ///
625    /// The tensor with the axes flipped.
626    ///
627    /// # Example
628    ///
629    /// ```rust
630    /// use burn_tensor::backend::Backend;
631    /// use burn_tensor::Tensor;
632    ///
633    /// fn example<B: Backend>() {
634    ///     let device = Default::default();
635    ///     // Create a 2D tensor with dimensions [4, 3]
636    ///     let tensor = Tensor::<B, 2>::from_data(
637    ///         [
638    ///             [3.0, 4.9, 2.0],
639    ///             [2.0, 1.9, 3.0],
640    ///             [4.0, 5.9, 8.0],
641    ///             [1.4, 5.8, 6.0],
642    ///         ],
643    ///         &device,
644    ///     );
645    ///
646    ///     // Flip the elements in dimensions 0 and 1:
647    ///     // [[6.0, 5.8, 1.4],
648    ///     //  [8.0, 5.9, 4.0],
649    ///     //  [3.0, 1.9, 2.0],
650    ///     //  [2.0, 4.9, 3.0]]
651    ///     // The resulting tensor will have dimensions [4, 3].
652    ///     let flipped = tensor.flip([0, 1]);
653    ///     println!("{flipped}");
654    /// }
655    /// ```
656    pub fn flip<const N: usize>(self, axes: [isize; N]) -> Tensor<B, D, K> {
657        // Convert the axes to usize and handle negative values without using vector
658        let mut transformed_axes: [usize; N] = [0; N];
659        for (i, &x) in axes.iter().enumerate() {
660            transformed_axes[i] = if x < 0 {
661                (D as isize + x) as usize
662            } else {
663                x as usize
664            };
665        }
666
667        // Check if the axes are valid
668        check!(TensorCheck::flip(D, &transformed_axes));
669
670        Tensor::new(K::flip(self.primitive, &transformed_axes))
671    }
672
673    /// Flatten the tensor along a given range of dimensions.
674    ///
675    /// This function collapses the specified range of dimensions into a single dimension,
676    /// effectively flattening the tensor in that range.
677    ///
678    /// # Arguments
679    ///
680    /// - `start_dim`: The starting dimension of the range to be flattened,
681    ///   supports negative indexing.
682    /// - `end_dim`: The ending dimension of the range to be flattened (inclusive),
683    ///   supports negative indexing.
684    ///
685    /// # Type Parameters
686    ///
687    /// - `D2`: The resulting number of dimensions in the flattened tensor.
688    ///
689    /// # Returns
690    ///
691    /// A new `Tensor<B, D2, K>` instance with the specified range of dimensions flattened.
692    ///
693    /// # Example
694    ///
695    /// ```rust
696    ///
697    /// use burn_tensor::backend::Backend;
698    /// use burn_tensor::{Tensor, Shape};
699    ///
700    /// fn example<B: Backend>() {
701    ///     let device = Default::default();
702    ///     // Create a 3D tensor with dimensions [2, 3, 4]
703    ///     let tensor = Tensor::<B, 3>::ones(Shape::new([2, 3, 4]), &device);
704    ///
705    ///     // Flatten the tensor from dimensions 1 to 2 (inclusive).
706    ///     // The resulting tensor will have dimensions [2, 12]
707    ///     let flattened: Tensor<B, 2> = tensor.flatten(1, 2);
708    ///     println!("{flattened}");
709    /// }
710    /// ```
711    pub fn flatten<const D2: usize>(
712        self,
713        start_dim: impl AsIndex,
714        end_dim: impl AsIndex,
715    ) -> Tensor<B, D2, K> {
716        let start_dim = start_dim.expect_dim_index(D);
717        let end_dim = end_dim.expect_dim_index(D);
718        check!(TensorCheck::flatten::<D, D2>(start_dim, end_dim));
719        let new_shape = self.shape().flatten_dims(start_dim, end_dim);
720
721        Tensor::new(K::reshape(self.primitive, new_shape))
722    }
723
724    /// Squeeze the tensor along all dimensions, removing dimensions
725    /// of size one, and effectively reducing the rank of the tensor.
726    ///
727    /// # Type Parameters
728    ///
729    ///  - `D2`: The resulting number of dimensions in the squeezed tensor.
730    ///
731    /// # Returns
732    ///
733    /// A new `Tensor<B, D2, K>` instance with the specified dimension removed.
734    ///
735    /// # Example
736    ///
737    /// ```rust
738    ///
739    /// use burn_tensor::backend::Backend;
740    /// use burn_tensor::{Tensor, Shape};
741    ///
742    /// fn example<B: Backend>() {
743    ///     let device = Default::default();
744    ///     // Create a 4D tensor with dimensions [1, 3, 1, 3]
745    ///     let tensor = Tensor::<B, 4>::from_data(
746    ///         [[[[3.0, 4.9, 2.0]], [[2.0, 1.9, 3.0]], [[4.0, 5.9, 8.0]]]],
747    ///         &device,
748    ///     );
749    ///
750    ///     // Squeeze the tensor dimensions.
751    ///     // The resulting tensor will have dimensions [3, 3].
752    ///     let squeezed = tensor.squeeze::<2>();
753    ///     println!("{squeezed}");
754    /// }
755    /// ```
756    pub fn squeeze<const D2: usize>(self) -> Tensor<B, D2, K> {
757        let new_dims = self
758            .shape()
759            .dims
760            .iter()
761            .filter_map(|&dim| if dim == 1 { None } else { Some(dim) })
762            .collect::<Vec<_>>();
763        check!(TensorCheck::squeeze_dims_len::<D2>(new_dims.len()));
764
765        Tensor::new(K::reshape(self.primitive, new_dims.into()))
766    }
767
768    /// Squeeze the tensor along the given dimension, removing the specified dimension
769    /// of size one, and effectively reducing the rank of the tensor by one.
770    ///
771    /// # Arguments
772    ///
773    /// - `dim`: The dimension to be squeezed.
774    ///
775    /// # Type Parameters
776    ///
777    ///  - `D2`: The resulting number of dimensions in the squeezed tensor.
778    ///
779    /// # Panics
780    ///
781    /// If the size in the squeezed dimension is not 1.
782    ///
783    /// # Returns
784    ///
785    /// A new `Tensor<B, D2, K>` instance with the specified dimension removed.
786    ///
787    /// # Example
788    ///
789    /// ```rust
790    ///
791    /// use burn_tensor::backend::Backend;
792    /// use burn_tensor::{Tensor, Shape};
793    ///
794    /// fn example<B: Backend>() {
795    ///     let device = Default::default();
796    ///     // Create a 3D tensor with dimensions [3, 1, 3]
797    ///     let tensor = Tensor::<B, 3>::from_data(
798    ///         [[[3.0, 4.9, 2.0]], [[2.0, 1.9, 3.0]], [[4.0, 5.9, 8.0]]],
799    ///         &device,
800    ///     );
801    ///
802    ///     // Squeeze the dimension 1.
803    ///     // The resulting tensor will have dimensions [3, 3].
804    ///     let squeezed = tensor.squeeze_dim::<2>(1);
805    ///     println!("{squeezed}");
806    /// }
807    /// ```
808    pub fn squeeze_dim<const D2: usize>(self, dim: usize) -> Tensor<B, D2, K> {
809        check!(TensorCheck::squeeze::<D2>(dim, &self.shape().dims));
810
811        let current_dims = self.shape().dims;
812        let mut new_dims: [usize; D2] = [0; D2];
813
814        new_dims[..dim].copy_from_slice(&current_dims[..dim]);
815        new_dims[dim..].copy_from_slice(&current_dims[dim + 1..]);
816
817        check!(TensorCheck::squeeze_dims_len::<D2>(new_dims.len()));
818        Tensor::new(K::reshape(self.primitive, new_dims.into()))
819    }
820
821    /// Removes specified dimensions of size 1 from a tensor's shape. This function takes a tensor and
822    /// an array of dimensions (`dims`) to be squeezed. If `dims` is provided, only the dimensions
823    /// specified in this array will be removed. Each dimension in `dims` should correspond to a size of 1
824    /// in the tensor; otherwise, the dimension will not be squeezed. If `dims` is empty, all single-dimensional entries
825    /// in the tensor will be removed. If entries in `dims` are negative, then dimensions will be counted
826    /// from the back.
827    ///
828    /// # Arguments
829    ///
830    /// - `dims`: The dimension(s) to be squeezed.
831    ///
832    /// # Type Parameters
833    ///
834    ///  - `D2`: The resulting number of dimensions in the squeezed tensor.
835    ///
836    /// # Returns
837    ///
838    /// A new `Tensor<B, D2, K>` instance with the specified dimensions removed.
839    ///
840    /// # Example
841    ///
842    /// ```rust
843    ///
844    /// use burn_tensor::backend::Backend;
845    /// use burn_tensor::{Tensor, Shape};
846    ///
847    /// fn example<B: Backend>() {
848    ///     let device = Default::default();
849    ///     // Create a 4D tensor with dimensions [2, 1, 4, 1]
850    ///     let tensor = Tensor::<B, 4>::ones(Shape::new([2, 1, 4, 1]), &device);
851    ///
852    ///     // Squeeze the dimensions 1 and 3.
853    ///     // The resulting tensor will have dimensions [2, 4].
854    ///     let squeezed: Tensor<B, 2> = tensor.squeeze_dims(&[1, 3]);
855    ///     println!("{squeezed}");
856    /// }
857    /// ```
858    pub fn squeeze_dims<const D2: usize>(self, dims: &[isize]) -> Tensor<B, D2, K> {
859        let current_dims = self.shape().dims;
860        let mut dim_indices: Vec<usize>;
861
862        // Check if dims is empty, if yes then assign dim_indices all single-dimensional entries
863        if dims.is_empty() {
864            dim_indices = current_dims
865                .iter()
866                .enumerate()
867                .filter_map(|(index, &dim)| if dim == 1 { Some(index) } else { None })
868                .collect();
869        } else {
870            // If negative dims, count from the back
871            dim_indices = dims
872                .iter()
873                .map(|&d| {
874                    if d < 0 {
875                        (current_dims.len() as isize + d) as usize
876                    } else {
877                        d as usize
878                    }
879                })
880                .collect();
881        }
882
883        // Sort indices and remove duplicates
884        dim_indices.sort_unstable();
885        dim_indices.dedup();
886
887        // Make sure squeeze_dims doesn't result in a tensor with < 1 dimensions
888        check!(TensorCheck::squeeze_dims_input::<D2>(
889            &dim_indices,
890            &current_dims
891        ));
892
893        // Calculate new dimensions
894        let mut new_dims = Vec::new();
895        for (index, &dim_size) in current_dims.iter().enumerate() {
896            // Exclude the dimension if it's explicitly marked for squeezing
897            if dim_indices.contains(&index) {
898                check!(TensorCheck::squeeze::<D2>(index, &current_dims));
899                continue;
900            }
901            new_dims.push(dim_size);
902        }
903
904        // Check that after squeezing, we still respect the D2 size
905        check!(TensorCheck::squeeze_dims_len::<D2>(new_dims.len()));
906
907        Tensor::new(K::reshape(self.primitive, new_dims.into()))
908    }
909
910    /// Unsqueeze the current tensor. Create new leading dimensions to fit the given size.
911    ///
912    /// # Type Parameters
913    ///
914    ///  - `D2`: The resulting number of dimensions in the unsqueezed tensor.
915    ///
916    /// # Panics
917    ///
918    /// If the output size `D2` is smaller than the current number of dimensions.
919    ///
920    /// # Returns
921    ///
922    /// A new `Tensor<B, D2, K>` instance with the specified dimensions added.
923    ///
924    /// # Example
925    ///
926    /// ```rust
927    /// use burn_tensor::backend::Backend;
928    /// use burn_tensor::{Tensor, Shape};
929    ///
930    /// fn example<B: Backend>() {
931    ///     let device = Default::default();
932    ///     // Create a 2D tensor with dimensions [3, 3]
933    ///     let tensor = Tensor::<B, 2>::ones(Shape::new([3, 3]), &device);
934    ///     // Unsqueeze the tensor up to 4 dimensions.
935    ///     // The resulting tensor will have dimensions [1, 1, 3, 3].
936    ///     let unsqueezed = tensor.unsqueeze::<4>();
937    ///     println!("{unsqueezed}");
938    /// }
939    /// ```
940    pub fn unsqueeze<const D2: usize>(self) -> Tensor<B, D2, K> {
941        check!(TensorCheck::unsqueeze::<D, D2>());
942
943        let mut dims = [1; D2];
944        let num_ones = D2 - D;
945        let shape = self.shape();
946
947        dims[num_ones..(D + num_ones)].copy_from_slice(&shape[..D]);
948
949        let shape = Shape::new(dims);
950        self.reshape(shape)
951    }
952
953    /// Creates a new tensor with a dimension of size one inserted at the specified position.
954    ///
955    /// # Example
956    ///
957    /// ```rust
958    /// use burn_tensor::backend::Backend;
959    /// use burn_tensor::{Tensor, Shape};
960    ///
961    /// fn example<B: Backend>() {
962    ///     let device = Default::default();
963    ///     // Create a 2D tensor with dimensions [3, 3]
964    ///     let tensor = Tensor::<B, 2>::ones(Shape::new([3, 3]), &device);
965    ///     // Unsqueeze the dimension 1.
966    ///     // The resulting tensor will have dimensions [3, 1, 3].
967    ///     let unsqueezed: Tensor<B, 3> = tensor.unsqueeze_dim(1);
968    ///     println!("{unsqueezed}");
969    /// }
970    /// ```
971    pub fn unsqueeze_dim<const D2: usize>(self, dim: usize) -> Tensor<B, D2, K> {
972        check!(TensorCheck::unsqueeze_dim::<D, D2>(dim));
973
974        let mut dims = [1; D2];
975        let shape = self.shape();
976
977        dims[0..dim].copy_from_slice(&shape[0..dim]);
978
979        if dim < D {
980            dims[dim] = 1;
981            dims[(dim + 1)..].copy_from_slice(&shape[dim..]);
982        } else {
983            dims[dim] = 1;
984        }
985
986        let shape = Shape::new(dims);
987        self.reshape(shape)
988    }
989
990    /// Creates a new tensor with added dimensions of size one inserted at the specified indices.
991    /// The indices can be negative, in which case they are counted from the last to the first dimension.
992    /// the axes can contain duplicates, in which case the number of dimensions inserted at the index
993    /// is the number of duplicates.
994    /// # Example
995    ///
996    /// ```rust
997    /// use burn_tensor::backend::Backend;
998    /// use burn_tensor::{Tensor, Shape};
999    ///
1000    /// fn example<B: Backend>() {
1001    ///     let device = Default::default();
1002    ///     // Create a 3D tensor with dimensions [3, 4, 5]
1003    ///     let tensor = Tensor::<B, 3>::ones(Shape::new([3, 4, 5]), &device);
1004    ///     // Unsqueeze the leading dimension (0) once and the trailing dimension (-1) twice.
1005    ///     // The resulting tensor will have dimensions [1, 3, 4, 5, 1, 1].
1006    ///     let unsqueezed: Tensor<B, 6> = tensor.unsqueeze_dims(&[0, -1, -1]);
1007    ///     println!("{unsqueezed}");
1008    /// }
1009    /// ```
1010    pub fn unsqueeze_dims<const D2: usize>(self, axes: &[impl AsIndex]) -> Tensor<B, D2, K> {
1011        let mut new_dims = [1; D2];
1012        let old_dims = self.shape().dims;
1013        //for checking if the dimension is in the acceptable range
1014
1015        //part 1: convert the negative indices to positive
1016        let mut neg_offset = D2;
1017        let mut dim_indices = axes
1018            .iter()
1019            .map(|d| {
1020                let d = d.as_index();
1021                // check if the dimension is in the acceptable range
1022                check!(TensorCheck::unsqueeze_dims::<{ D2 }>(d));
1023                (if d < 0 {
1024                    neg_offset -= 1; // handle multiple negative indices (decrease dim value in reverse)
1025                    d + neg_offset as isize + 1
1026                } else {
1027                    d
1028                }) as usize
1029            })
1030            .collect::<Vec<usize>>();
1031
1032        //sort the indices
1033        dim_indices.sort_unstable();
1034
1035        //Now use this to copy the chunks of the dims
1036        let mut prev_idx: usize = 0;
1037        let mut current_left_b: usize = 0;
1038        let mut current_right_b: usize = 0;
1039        let mut offset: usize = 0;
1040        dim_indices.iter().for_each(|d| {
1041            //check if there is space for at least one dimension
1042            if prev_idx < *d {
1043                current_right_b = *d - offset;
1044                //copy the chunks of the dims
1045                if current_right_b < D {
1046                    new_dims[prev_idx..*d]
1047                        .copy_from_slice(&old_dims[current_left_b..current_right_b]);
1048                } else {
1049                    new_dims[prev_idx..*d].copy_from_slice(&old_dims[current_left_b..]);
1050                }
1051                prev_idx = *d + 1;
1052                //offset is equal to the number of extracted elements from the original shape
1053                offset += current_right_b - current_left_b;
1054                current_left_b = current_right_b;
1055            } else {
1056                //it's sorted so the only reason this would happen
1057                //is if multiple indices are the same
1058                prev_idx += 1;
1059            }
1060        });
1061        //copy over anything past the index of the last new dimension
1062        if current_left_b < D {
1063            new_dims[prev_idx..].copy_from_slice(&old_dims[current_left_b..]);
1064        }
1065
1066        //lastly, create the shape and reshape
1067        let shape = Shape::new(new_dims);
1068        self.reshape(shape)
1069    }
1070
1071    /// Roll operation along a specific dimension; wrapping around the elements.
1072    ///
1073    /// ## Parameters
1074    ///
1075    /// - `shift`: The roll extent; supports negative values and wraps around.
1076    /// - `dim`: The dimension to roll; supports negative indexing.
1077    ///
1078    /// ## Returns
1079    ///
1080    /// A new tensor with the specified dimension rolled by the given shift amount.
1081    pub fn roll_dim<Shift, Dim>(self, shift: Shift, dim: Dim) -> Self
1082    where
1083        Shift: AsIndex,
1084        Dim: AsIndex,
1085    {
1086        let dim = dim.expect_dim_index(D);
1087        let size = self.shape().dims[dim];
1088        if size == 0 {
1089            // If the dimension is empty, return the tensor as is.
1090            return self;
1091        }
1092
1093        let shift = wrap_index(shift, size);
1094        if shift == 0 {
1095            // If the shift is zero, return the tensor as is.
1096            return self;
1097        }
1098
1099        self.unchecked_roll_dim(shift, dim)
1100    }
1101
1102    /// Internal implementation of `roll_dim` that does not canonicalize dimensions or shifts.
1103    ///
1104    /// ## Parameters
1105    ///
1106    /// - `shift`: The number of positions to shift; must be (0 < shift < size).
1107    /// - `dim`: The dimension to roll; must be a valid index for the tensor's shape.
1108    ///
1109    /// ## Returns
1110    ///
1111    /// A new tensor with the specified dimension rolled by the given shift amount.
1112    #[inline(always)]
1113    fn unchecked_roll_dim(self, shift: usize, dim: usize) -> Self {
1114        #[cfg(debug_assertions)]
1115        {
1116            let size = self.shape().dims[dim];
1117            assert!(
1118                0 < shift && shift < size,
1119                "Expected: 0 < shift < size: found shift={shift}, size={size}",
1120            );
1121            assert!(
1122                dim < self.shape().num_dims(),
1123                "Expected: dim < num_dims: found dim={dim}, num_dims={size}",
1124            );
1125        }
1126
1127        Tensor::cat(
1128            vec![
1129                self.clone().slice_dim(dim, shift..),
1130                self.slice_dim(dim, ..shift),
1131            ],
1132            dim,
1133        )
1134    }
1135
1136    /// Roll operation.
1137    ///
1138    /// Note: unlike ``pytorch``, `dims` and `shifts` must have the same length.
1139    ///
1140    /// A given `dim` may be rolled multiple times, and the shifts will be applied sequentially.
1141    ///
1142    /// ## Parameters
1143    ///
1144    /// - `shifts`: A slice of shifts corresponding to each dimension;
1145    ///   supports negative values and wraps around.
1146    /// - `dims`: A slice of dimensions to roll; supports negative indexing.
1147    ///
1148    /// ## Returns
1149    ///
1150    /// A new tensor with the specified dimensions rolled by the given shifts.
1151    pub fn roll<Shift, Dim>(self, shifts: &[Shift], dims: &[Dim]) -> Self
1152    where
1153        Shift: AsIndex,
1154        Dim: AsIndex,
1155    {
1156        assert_eq!(
1157            dims.len(),
1158            shifts.len(),
1159            "Dimensions and shifts must align; found dims={dims:#?}, shifts={shifts:#?}",
1160        );
1161
1162        // This is a fair amount of complexity, which could be replaced
1163        // by a simple canonicalization of `dims` and wrapping of `shifts`.
1164        // The work is done here to ensure that any roll operation
1165        // which could be a no-op is a no-op; simplifying the accounting
1166        // needed by backend-specific implementations of the inner roll op.
1167
1168        let item_count = dims.len();
1169
1170        let shape = self.shape().dims;
1171
1172        // Accumulate the effective shifts for each dimension.
1173        let mut accumulated_shifts: Vec<isize> = vec![0; shape.len()];
1174        for i in 0..item_count {
1175            let dim = dims[i].expect_dim_index(D);
1176            accumulated_shifts[dim] += shifts[i].as_index();
1177        }
1178
1179        // Do this after we've checked the validity of `dims` and `shifts`.
1180        if self.shape().num_elements() == 0 {
1181            // If the tensor is empty, return it as is.
1182            return self;
1183        }
1184
1185        // Wrap the accumulated shifts, and filter out empty dimensions.
1186        let mut effective_dims: Vec<usize> = Vec::with_capacity(item_count);
1187        let mut effective_shifts: Vec<usize> = Vec::with_capacity(item_count);
1188        for dim in 0..shape.len() {
1189            // `wrap_index` should inline, and has a fast-exit path for zero shifts.
1190            let shift = wrap_index(accumulated_shifts[dim], shape[dim]);
1191            if shift == 0 {
1192                continue;
1193            }
1194
1195            effective_dims.push(dim);
1196            effective_shifts.push(shift);
1197        }
1198
1199        // If no shifts are needed, return the original tensor.
1200        if effective_shifts.is_empty() {
1201            return self;
1202        }
1203
1204        // At this point:
1205        // - `dims` contains the effective dimensions to roll, in index order,
1206        // - `shifts` contains the effective usize shifts for each dimension.
1207        // - Every shift is non-zero, and less than the size of the corresponding dimension.
1208        self.unchecked_roll(&effective_shifts, &effective_dims)
1209    }
1210
1211    /// `roll` internal implementation.
1212    ///
1213    /// ## Parameters
1214    ///
1215    /// - `shifts`: A slice of shifts corresponding to each dimension;
1216    ///   must be non-empty, the same length as `dims`, and all ``1..<size>``.
1217    /// - `dims`: A slice of dimensions to roll; must be non-empty;
1218    ///   the same length as `shifts`, and must not contain repeats.
1219    ///
1220    /// ## Panics
1221    ///
1222    /// Panics if the shifts and dimensions do not align, or if dimensions contain repeats.
1223    ///
1224    /// ## Returns
1225    ///
1226    /// A new tensor with the specified dimensions rolled by the given shifts.
1227    #[inline(always)]
1228    fn unchecked_roll(self, shifts: &[usize], dims: &[usize]) -> Self {
1229        #[cfg(debug_assertions)]
1230        {
1231            assert!(!shifts.is_empty());
1232            assert_eq!(
1233                shifts.len(),
1234                dims.len(),
1235                "Shifts and dimensions must align; found {} shifts and {} dims",
1236                shifts.len(),
1237                dims.len()
1238            );
1239
1240            let mut unique_dims = dims.to_vec();
1241            unique_dims.dedup();
1242
1243            assert_eq!(
1244                unique_dims.len(),
1245                dims.len(),
1246                "Dimensions must not contain repeats; found {} unique dims and {} total dims",
1247                unique_dims.len(),
1248                dims.len()
1249            )
1250        }
1251
1252        let x = self.unchecked_roll_dim(shifts[0], dims[0]);
1253
1254        if dims.len() == 1 {
1255            x
1256        } else {
1257            x.unchecked_roll(&shifts[1..], &dims[1..])
1258        }
1259    }
1260
1261    /// Returns a tensor containing the elements selected from the given slices.
1262    ///
1263    /// This method provides flexible tensor slicing with support for various range types,
1264    /// negative indices, and stepped slicing. The method accepts both single slices and
1265    /// arrays of slices, with the [`s!`] macro providing convenient syntax for complex patterns.
1266    ///
1267    /// # Arguments
1268    ///
1269    /// * `slices` - Can be:
1270    ///   - A single range for 1D slicing (e.g., `0..5`, `..`, `2..`)
1271    ///   - An array of ranges (e.g., `[0..2, 1..4]`)
1272    ///   - The [`s!`] macro output for advanced slicing with steps
1273    ///   - a `&Vec<Slice>` or `&[Slice]`
1274    ///
1275    /// # Behavior
1276    ///
1277    /// - Supports partial and full slicing in any number of dimensions
1278    /// - Handles negative indices by wrapping from the end (-1 is the last element)
1279    /// - Automatically clamps ranges that exceed tensor dimensions
1280    /// - Supports stepped slicing for selecting every nth element
1281    /// - Negative steps reverse the selection order
1282    ///
1283    /// # Panics
1284    ///
1285    /// - If the number of slices exceeds the tensor's dimensions
1286    /// - If a range is descending (e.g., 2..1) or empty (e.g., 1..1) without negative step
1287    /// - If a step is zero
1288    ///
1289    /// # Examples
1290    ///
1291    /// ```rust
1292    /// use burn_tensor::backend::Backend;
1293    /// use burn_tensor::{Tensor, Shape, s};
1294    ///
1295    /// fn example<B: Backend>() {
1296    ///     let device = B::Device::default();
1297    ///
1298    ///     // Single dimension slicing - no brackets needed!
1299    ///     let tensor = Tensor::<B, 1, burn_tensor::Int>::arange(0..10, &device);
1300    ///     let slice = tensor.clone().slice(2..8);  // Simple range
1301    ///     assert_eq!(slice.into_data().to_vec::<i32>().unwrap(), vec![2, 3, 4, 5, 6, 7]);
1302    ///
1303    ///     // Using s! macro for single dimension with step
1304    ///     let slice = tensor.clone().slice(s![0..10;2]);  // Every 2nd element
1305    ///     assert_eq!(slice.into_data().to_vec::<i32>().unwrap(), vec![0, 2, 4, 6, 8]);
1306    ///
1307    ///     // Reverse a dimension with negative step
1308    ///     let slice = tensor.slice(s![..;-1]);  // Reverse entire tensor
1309    ///     assert_eq!(slice.into_data().to_vec::<i32>().unwrap(), vec![9, 8, 7, 6, 5, 4, 3, 2, 1, 0]);
1310    ///
1311    ///     // Multi-dimensional slicing
1312    ///     let tensor = Tensor::<B, 2>::ones(Shape::new([4, 6]), &device);
1313    ///
1314    ///     // Array syntax for simple ranges
1315    ///     let slice = tensor.clone().slice([1..3, 2..5]);
1316    ///     assert_eq!(slice.dims(), [2, 3]);
1317    ///
1318    ///     // Advanced multi-dimensional with s! macro
1319    ///     let slice = tensor.clone().slice(s![0..4;2, ..;-1]);  // Every 2nd row, reverse columns
1320    ///     assert_eq!(slice.dims(), [2, 6]);
1321    ///
1322    ///     // Complex 3D example with mixed slice types
1323    ///     let tensor = Tensor::<B, 3>::ones(Shape::new([4, 6, 8]), &device);
1324    ///     let slice = tensor.slice(s![1..3, ..;2, -3..]);  // Rows 1-2, every 2nd col, last 3 depth
1325    ///     assert_eq!(slice.dims(), [2, 3, 3]);
1326    ///
1327    ///     // Using negative indices
1328    ///     let tensor = Tensor::<B, 2>::ones(Shape::new([4, 6]), &device);
1329    ///     let slice = tensor.slice(s![-2.., ..-1]);  // Last 2 rows, all but last column
1330    ///     assert_eq!(slice.dims(), [2, 5]);
1331    /// }
1332    /// ```
1333    ///
1334    /// # See Also
1335    ///
1336    /// - [`s!`] - The recommended macro for creating complex slice specifications
1337    /// - [`slice_assign`](Self::slice_assign) - Assign values to a slice
1338    /// - [`slice_fill`](Self::slice_fill) - Fill a slice with a constant value
1339    /// - [`slice_dim`](Self::slice_dim) - Slice a single dimension
1340    ///
1341    /// [`s!`]: crate::s!
1342    pub fn slice<S>(self, slices: S) -> Self
1343    where
1344        S: SliceArg,
1345    {
1346        let shape = self.shape();
1347        let slices = slices.into_slices(&shape);
1348
1349        // Validate slices
1350        check!(TensorCheck::slice::<D>(&shape, &slices));
1351
1352        // Calculate output shape and check for empty slices
1353        let mut output_dims = shape.dims.clone();
1354        for (dim, slice) in slices.iter().enumerate() {
1355            output_dims[dim] = slice.output_size(shape.dims[dim]);
1356        }
1357
1358        // Return empty tensor if any dimension is 0 (empty slice)
1359        if output_dims.contains(&0) {
1360            return Self::empty(output_dims, &self.device());
1361        }
1362        Self::new(K::slice(self.primitive, &slices))
1363    }
1364
1365    /// Assigns values to a slice of the tensor and returns the updated tensor.
1366    ///
1367    /// This method supports advanced slicing with steps, including negative steps for reverse
1368    /// assignment. Like `slice`, it accepts both single slices and arrays, with the [`s!`] macro
1369    /// providing powerful syntax for complex patterns.
1370    ///
1371    /// # Arguments
1372    ///
1373    /// * `slices` - Slice specification (same format as `slice` method)
1374    /// * `values` - Tensor with values to assign (must match slice dimensions)
1375    ///
1376    /// # Panics
1377    ///
1378    /// - If slices exceed tensor dimensions
1379    /// - If values dimensions don't match the selected slice shape
1380    /// - If a step is zero
1381    ///
1382    /// # Examples
1383    ///
1384    /// ```rust
1385    /// use burn_tensor::backend::Backend;
1386    /// use burn_tensor::{Tensor, s};
1387    ///
1388    /// fn example<B: Backend>() {
1389    ///     let device = B::Device::default();
1390    ///
1391    ///     // Simple assignment to a sub-region
1392    ///     let mut tensor = Tensor::<B, 2>::zeros([4, 6], &device);
1393    ///     let values = Tensor::<B, 2>::ones([2, 3], &device);
1394    ///     tensor = tensor.slice_assign([1..3, 2..5], values);
1395    ///     // Now tensor[1..3, 2..5] contains ones
1396    ///
1397    ///     // Single dimension assignment with step
1398    ///     let mut tensor = Tensor::<B, 1>::zeros([10], &device);
1399    ///     let values = Tensor::<B, 1>::ones([5], &device);
1400    ///     tensor = tensor.slice_assign(s![0..10;2], values);
1401    ///     // Now every 2nd element is 1: [1, 0, 1, 0, 1, 0, 1, 0, 1, 0]
1402    ///
1403    ///     // Reverse assignment with negative step
1404    ///     let mut tensor = Tensor::<B, 1>::from_data([0.0, 1.0, 2.0, 3.0, 4.0], &device);
1405    ///     let values = Tensor::<B, 1>::from_data([10.0, 11.0, 12.0, 13.0, 14.0], &device);
1406    ///     tensor = tensor.slice_assign(s![..;-1], values);
1407    ///     // Assigns in reverse: [14, 13, 12, 11, 10]
1408    ///
1409    ///     // Complex multi-dimensional assignment
1410    ///     let mut tensor = Tensor::<B, 3>::zeros([4, 6, 8], &device);
1411    ///     let values = Tensor::<B, 3>::ones([2, 3, 3], &device);
1412    ///     tensor = tensor.slice_assign(s![0..4;2, ..;2, -3..], values);
1413    ///     // Assigns to every 2nd row, every 2nd column, last 3 in depth
1414    ///
1415    ///     // Mixed syntax example
1416    ///     let mut tensor = Tensor::<B, 2>::zeros([8, 8], &device);
1417    ///     let pattern = Tensor::<B, 2>::ones([4, 4], &device);
1418    ///     tensor = tensor.slice_assign(s![..;2, ..;2], pattern);
1419    ///     // Creates a checkerboard pattern with ones
1420    /// }
1421    /// ```
1422    ///
1423    /// # See Also
1424    ///
1425    /// - [`s!`] - The recommended macro for creating complex slice specifications
1426    /// - [`slice`](Self::slice) - Extract a slice from a tensor
1427    /// - [`slice_fill`](Self::slice_fill) - Fill a slice with a constant value
1428    ///
1429    /// [`s!`]: crate::s!
1430    pub fn slice_assign<S>(self, slices: S, values: Self) -> Self
1431    where
1432        S: SliceArg,
1433    {
1434        let shape = self.shape();
1435        let slices = slices.into_slices(&shape);
1436
1437        // Check if any slice produces 0 elements (empty assignment).
1438        // Empty assignments are no-ops and would cause issues in backend implementations.
1439        let is_empty_assignment = slices
1440            .iter()
1441            .enumerate()
1442            .any(|(i, slice)| slice.output_size(shape.dims[i]) == 0);
1443
1444        if is_empty_assignment {
1445            return self;
1446        }
1447
1448        check!(TensorCheck::slice_assign::<D>(
1449            &shape,
1450            &values.shape(),
1451            &slices
1452        ));
1453
1454        Self::new(K::slice_assign(self.primitive, &slices, values.primitive))
1455    }
1456
1457    /// Fills a slice of the tensor with a constant value and returns the updated tensor.
1458    ///
1459    /// Like other slice methods, accepts both single slices and arrays. However, this method
1460    /// currently **does not support stepped slicing** - use [`slice_assign`](Self::slice_assign)
1461    /// with a constant tensor for stepped patterns.
1462    ///
1463    /// # Arguments
1464    ///
1465    /// * `slices` - Slice specification (same format as `slice` method, but no steps)
1466    /// * `value` - The value to fill the slice with
1467    ///
1468    /// # Panics
1469    ///
1470    /// - If slices exceed tensor dimensions
1471    /// - If any slice has a step != 1 (not yet supported)
1472    ///
1473    /// # Examples
1474    ///
1475    /// ```rust
1476    /// use burn_tensor::backend::Backend;
1477    /// use burn_tensor::{Tensor, s};
1478    ///
1479    /// fn example<B: Backend>() {
1480    ///     let device = B::Device::default();
1481    ///
1482    ///     // Simple fill for a single dimension
1483    ///     let mut tensor = Tensor::<B, 1>::zeros([10], &device);
1484    ///     tensor = tensor.slice_fill(2..5, 1.0);
1485    ///     // Now tensor is [0, 0, 1, 1, 1, 0, 0, 0, 0, 0]
1486    ///
1487    ///     // Multi-dimensional fill
1488    ///     let mut tensor = Tensor::<B, 2>::zeros([4, 6], &device);
1489    ///     tensor = tensor.slice_fill([1..3, 2..5], -1.0);
1490    ///     // Fills the rectangle at rows 1-2, columns 2-4 with -1
1491    ///
1492    ///     // Using negative indices
1493    ///     let mut tensor = Tensor::<B, 1>::zeros([10], &device);
1494    ///     tensor = tensor.slice_fill(-3.., 2.0);
1495    ///     // Fills the last 3 elements with 2.0
1496    ///
1497    ///     // Complex multi-dimensional example
1498    ///     let mut tensor = Tensor::<B, 3>::ones([4, 6, 8], &device);
1499    ///     tensor = tensor.slice_fill(s![1..3, .., -2..], 0.0);
1500    ///     // Sets rows 1-2, all columns, last 2 in depth to 0
1501    ///
1502    ///     // Stepped slicing is supported
1503    ///     let mut tensor = Tensor::<B, 1>::zeros([10], &device);
1504    ///     tensor = tensor.slice_fill(s![0..10;2], 1.0);
1505    ///     // Now every 2nd element is 1: [1, 0, 1, 0, 1, 0, 1, 0, 1, 0]
1506    /// }
1507    /// ```
1508    ///
1509    /// # See Also
1510    ///
1511    /// - [`s!`] - The macro for creating slice specifications with steps
1512    /// - [`slice`](Self::slice) - Extract a slice from a tensor
1513    /// - [`slice_assign`](Self::slice_assign) - Assign tensor values to a slice
1514    ///
1515    /// [`s!`]: crate::s!
1516    pub fn slice_fill<S, E: ElementConversion>(self, slices: S, value: E) -> Self
1517    where
1518        S: SliceArg,
1519    {
1520        let shape = self.shape();
1521        let slices = slices.into_slices(&shape);
1522
1523        check!(TensorCheck::slice::<D>(&shape, &slices));
1524
1525        let slice_shape = shape.slice(&slices).unwrap();
1526        let value = Tensor::<B, 1, K>::from_data_dtype(
1527            [value.elem::<K::Elem>()],
1528            &self.device(),
1529            self.dtype(),
1530        );
1531        let value = value.expand(slice_shape);
1532        self.slice_assign(&slices, value)
1533    }
1534
1535    /// Returns a new tensor with the specified dimension sliced.
1536    ///
1537    /// # Arguments
1538    ///
1539    /// * `dim`: The dimension to slice.
1540    /// * `slice`: The slice specification for the dimension. Can be a range (e.g., `2..5`),
1541    ///   slice with step (via `s!` macro, e.g., `s![0..10;2]`), or any type that implements `Into<Slice>`.
1542    ///
1543    /// # Returns
1544    ///
1545    /// A new tensor with the specified dimension sliced.
1546    ///
1547    /// # Panics
1548    ///
1549    /// If the slice is out of bounds for the specified dimension.
1550    ///
1551    /// # Examples
1552    ///
1553    /// ```rust
1554    /// # use burn_tensor::{Tensor, s};
1555    /// # use burn_tensor::backend::Backend;
1556    /// #
1557    /// # fn example<B: Backend>() {
1558    /// #     let device = B::Device::default();
1559    ///     let tensor = Tensor::<B, 3>::zeros([3, 4, 5], &device);
1560    ///
1561    ///     // Simple range slicing
1562    ///     let sliced = tensor.clone().slice_dim(1, 1..3);
1563    ///     assert_eq!(sliced.shape().dims, [3, 2, 5]);
1564    ///
1565    ///     // Slicing with step - take every 2nd element
1566    ///     let sliced = tensor.clone().slice_dim(2, s![0..5;2]);
1567    ///     assert_eq!(sliced.shape().dims, [3, 4, 3]); // Takes indices 0, 2, 4
1568    ///
1569    ///     // Reverse slicing with negative step
1570    ///     let sliced = tensor.clone().slice_dim(1, s![..;-1]);
1571    ///     assert_eq!(sliced.shape().dims, [3, 4, 5]); // Reverses dimension 1
1572    ///
1573    ///     // Select from index 2 with step 3
1574    ///     let sliced = tensor.clone().slice_dim(0, s![2..;3]);
1575    ///     assert_eq!(sliced.shape().dims, [1, 4, 5]); // Takes only index 2
1576    ///
1577    ///     // Select single index (reduces dimension to size 1)
1578    ///     let sliced = tensor.slice_dim(0, 1);
1579    ///     assert_eq!(sliced.shape().dims, [1, 4, 5]);
1580    /// # }
1581    /// ```
1582    ///
1583    /// # See Also
1584    ///
1585    /// - [`slice`](Self::slice) - Slice multiple dimensions simultaneously
1586    /// - [`s!`] - The macro for creating complex slice specifications
1587    ///
1588    /// [`s!`]: crate::s!
1589    pub fn slice_dim<S>(self, dim: usize, slice: S) -> Self
1590    where
1591        S: Into<Slice>,
1592    {
1593        check!(TensorCheck::check_dim::<D>(dim));
1594        let slice: Slice = slice.into();
1595
1596        let mut slices = vec![Slice::full(); D];
1597        slices[dim] = slice;
1598
1599        self.slice(&slices)
1600    }
1601
1602    /// Returns the device of the current tensor.
1603    pub fn device(&self) -> B::Device {
1604        K::device(&self.primitive)
1605    }
1606
1607    /// Move the tensor to the given device.
1608    pub fn to_device(self, device: &B::Device) -> Self {
1609        Self::new(K::to_device(self.primitive, device))
1610    }
1611
1612    /// Select tensor elements along the given dimension corresponding to the given indices.
1613    ///
1614    /// # Arguments
1615    ///
1616    /// * `dim` - The dimension to select from. Supports negative indexing.
1617    /// * `indices` - The indices of the elements to select.
1618    ///
1619    /// # Example
1620    ///
1621    /// ```rust
1622    /// use burn_tensor::backend::Backend;
1623    /// use burn_tensor::{Tensor, Int};
1624    ///
1625    /// fn example<B: Backend>() {
1626    ///   let device = B::Device::default();
1627    ///   let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [4.0, 5.0, 6.0]], &device);
1628    ///   let indices = Tensor::<B, 1, Int>::from_data([0], &device);
1629    ///   let tensor = tensor.select(0, indices);
1630    ///   println!("{tensor}");
1631    ///   //  [[1.0, -2.0, 3.0]]
1632    /// }
1633    /// ```
1634    pub fn select(self, dim: impl AsIndex, indices: Tensor<B, 1, Int>) -> Self {
1635        let dim = dim.expect_dim_index(D);
1636        check!(TensorCheck::select::<D>(dim));
1637        Self::new(K::select(self.primitive, dim, indices.primitive))
1638    }
1639
1640    /// Assign the selected elements along the given dimension corresponding to the given indices
1641    /// from the value tensor to the original tensor using sum reduction.
1642    ///
1643    /// # Note
1644    /// For booleans, the sum operator is logical or.
1645    ///
1646    /// # Arguments
1647    ///
1648    /// * `dim` - The dimension along which to select. Supports negative indexing.
1649    /// * `indices` - The indices to select from the tensor.
1650    /// * `values` - The values to assign to the selected indices.
1651    /// * `update` - The operation used to update the existing values at the indexed positions (e.g., add).
1652    ///
1653    /// # Example
1654    ///
1655    /// Example using a 3D tensor:
1656    ///
1657    /// `input[indices[i], j, k] += values[i, j, k]; // dim = 0`
1658    /// `input[i, indices[j], k] += values[i, j, k]; // dim = 1`
1659    /// `input[i, j, indices[k]] += values[i, j, k]; // dim = 2`
1660    /// `input[i, j, indices[k]] += values[i, j, k]; // dim = -1 (same as dim = 2)`
1661    ///
1662    /// # Warning
1663    ///
1664    /// Not all backends have runtime bound checks for the indices, so make sure they are valid.
1665    /// Otherwise, out of bounds indices could lead to unexpected results instead of panicking.
1666    pub fn select_assign(
1667        self,
1668        dim: impl AsIndex,
1669        indices: Tensor<B, 1, Int>,
1670        values: Tensor<B, D, K>,
1671        update: IndexingUpdateOp,
1672    ) -> Self {
1673        let dim = dim.expect_dim_index(D);
1674        check!(TensorCheck::select_assign::<D>(
1675            dim,
1676            &indices.shape(),
1677            &values.shape()
1678        ));
1679
1680        Self::new(K::select_assign(
1681            self.primitive,
1682            dim,
1683            indices.primitive,
1684            values.primitive,
1685            update,
1686        ))
1687    }
1688
1689    /// Update the given tensor with the value tensor where the mask is true.
1690    ///
1691    /// This is similar to [mask_fill](Tensor::mask_fill), however the value is a tensor instead of
1692    /// a scalar.
1693    ///
1694    /// # Example
1695    ///
1696    /// ```rust
1697    /// use burn_tensor::backend::Backend;
1698    /// use burn_tensor::{Tensor, Shape, Bool};
1699    ///
1700    /// fn example<B: Backend>() {
1701    ///   let device = B::Device::default();
1702    ///   let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
1703    ///   let mask = Tensor::<B, 2, Bool>::from_data([[true, false, true], [false, true, false]], &device);
1704    ///   let value = Tensor::<B, 2>::from_data([[2.0, 3.0, 4.0], [1.0, 2.0, 3.0]], &device);
1705    ///   let tensor = tensor.mask_where(mask, value);
1706    ///   println!("{tensor}");
1707    ///   // [[2.0, -2.0, 4.0], [5.0, 2.0, 6.0]]
1708    /// }
1709    /// ```
1710    pub fn mask_where(self, mask: Tensor<B, D, Bool>, value: Self) -> Self {
1711        Self::new(K::mask_where(
1712            self.primitive,
1713            mask.primitive,
1714            value.primitive,
1715        ))
1716    }
1717
1718    /// Update the given tensor with the value where the mask is true.
1719    ///
1720    /// This is similar to [mask_where](Tensor::mask_where), however the value is a scalar instead of
1721    /// a tensor.
1722    ///
1723    /// # Example
1724    ///
1725    /// ```rust
1726    /// use burn_tensor::backend::Backend;
1727    /// use burn_tensor::{Tensor, Shape, Bool};
1728    ///
1729    /// fn example<B: Backend>() {
1730    ///   let device = B::Device::default();
1731    ///   let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
1732    ///   let mask = Tensor::<B, 2, Bool>::from_data([[true, false, true], [false, true, false]], &device);
1733    ///   let tensor = tensor.mask_fill(mask, 3.0);
1734    ///   println!("{tensor}");
1735    ///   // [[3.0, -2.0, 3.0], [5.0, 3.0, 6.0]]
1736    /// }
1737    /// ```
1738    pub fn mask_fill<E: ElementConversion>(self, mask: Tensor<B, D, Bool>, value: E) -> Self {
1739        let value = Scalar::new(value, &self.dtype());
1740        Self::new(K::mask_fill(self.primitive, mask.primitive, value))
1741    }
1742
1743    /// Gather tensor elements corresponding to the given indices from the specified dim.
1744    ///
1745    /// Example using a 3D tensor:
1746    ///
1747    /// `output[i, j, k] = input[indices[i, j, k], j, k]; // dim = 0`
1748    /// `output[i, j, k] = input[i, indices[i, j, k], k]; // dim = 1`
1749    /// `output[i, j, k] = input[i, j, indices[i, j, k]]; // dim = 2`
1750    ///
1751    /// # Notes
1752    ///
1753    /// The index tensor should have the same shape as the original tensor except for the dim
1754    /// specified.
1755    ///
1756    /// # Warning
1757    /// Not all backends have runtime bound checks for the indices, so make sure the they are valid.
1758    /// Otherwise, out of bounds indices could lead to unexpected results instead of panicking.
1759    pub fn gather(self, dim: usize, indices: Tensor<B, D, Int>) -> Self {
1760        check!(TensorCheck::gather::<D>(
1761            dim,
1762            &self.shape(),
1763            &indices.shape()
1764        ));
1765
1766        Self::new(K::gather(dim, self.primitive, indices.primitive))
1767    }
1768
1769    /// Assign the gathered elements corresponding to the given indices along the specified dimension
1770    /// from the value tensor to the original tensor using sum reduction.
1771    ///
1772    /// Example using a 3D tensor:
1773    ///
1774    /// `input[indices[i, j, k], j, k] += values[i, j, k]; // dim = 0`
1775    /// `input[i, indices[i, j, k], k] += values[i, j, k]; // dim = 1`
1776    /// `input[i, j, indices[i, j, k]] += values[i, j, k]; // dim = 2`
1777    ///
1778    /// # Arguments
1779    /// * `dim` - The axis along which to scatter elements.
1780    /// * `indices` - The indices of the elements to scatter.
1781    /// * `values` - The values to scatter into the tensor.
1782    /// * `update` - The operation used to update the existing values at the indexed positions (e.g., add).
1783    ///
1784    /// # Notes
1785    ///
1786    /// The index tensor should have the same shape as the original tensor except for the specified
1787    /// dimension. The value and index tensors should have the same shape.
1788    ///
1789    /// Other references to the input tensor will not be modified by this operation.
1790    ///
1791    /// # Warning
1792    /// Not all backends have runtime bound checks for the indices, so make sure the they are valid.
1793    /// Otherwise, out of bounds indices could lead to unexpected results instead of panicking.
1794    pub fn scatter(
1795        self,
1796        dim: usize,
1797        indices: Tensor<B, D, Int>,
1798        values: Self,
1799        update: IndexingUpdateOp,
1800    ) -> Self {
1801        check!(TensorCheck::scatter::<D>(
1802            dim,
1803            &self.shape(),
1804            &indices.shape(),
1805            &values.shape()
1806        ));
1807
1808        Self::new(K::scatter(
1809            dim,
1810            self.primitive,
1811            indices.primitive,
1812            values.primitive,
1813            update,
1814        ))
1815    }
1816
1817    /// Converts the data of the current tensor.
1818    ///
1819    /// # Note
1820    ///
1821    /// For better performance, prefer using a [Transaction](crate::Transaction) when reading multiple
1822    /// tensors at once. This may improve laziness, especially if executed on a different
1823    /// thread in native environments.
1824    pub fn into_data(self) -> TensorData {
1825        self.try_into_data().expect(
1826            "Error while reading data: use `try_into_data` instead to catch the error at runtime",
1827        )
1828    }
1829
1830    /// Converts the data of the current tensor and returns any error that might have occurred since the
1831    /// last time the device was synchronized.
1832    ///
1833    /// # Note
1834    ///
1835    /// For better performance, prefer using a [Transaction](crate::Transaction) when reading multiple
1836    /// tensors at once. This may improve laziness, especially if executed on a different
1837    /// thread in native environments.
1838    pub fn try_into_data(self) -> Result<TensorData, ExecutionError> {
1839        crate::try_read_sync(self.into_data_async()).expect(
1840            "Failed to read tensor data synchronously.
1841        This can happen on platforms that don't support blocking futures like WASM.
1842        If possible, try using into_data_async instead.",
1843        )
1844    }
1845
1846    /// Converts the data of the current tensor.
1847    ///
1848    /// # Note
1849    ///
1850    /// For better performance, prefer using a [Transaction](crate::Transaction) when reading multiple
1851    /// tensors at once. This may improve laziness, especially if executed on a different
1852    /// thread in native environments.
1853    pub fn to_data(&self) -> TensorData {
1854        self.clone().into_data()
1855    }
1856
1857    /// Returns the data of the current tensor.
1858    pub async fn into_data_async(self) -> Result<TensorData, ExecutionError> {
1859        K::into_data_async(self.primitive).await
1860    }
1861
1862    /// Returns the data of the current tensor.
1863    pub async fn to_data_async(&self) -> Result<TensorData, ExecutionError> {
1864        self.clone().into_data_async().await
1865    }
1866
1867    /// Create a tensor from the given data on the given device.
1868    pub fn from_data<T>(data: T, device: &B::Device) -> Self
1869    where
1870        T: Into<TensorData>,
1871    {
1872        let data = data.into();
1873        check!(TensorCheck::creation_ops::<D>(
1874            "From Data",
1875            data.shape.as_slice()
1876        ));
1877        Self::new(K::from_data(data, device))
1878    }
1879
1880    /// Create a tensor from the given data on the given device enforcing the given data type.
1881    pub fn from_data_dtype<T>(data: T, device: &B::Device, dtype: DType) -> Self
1882    where
1883        T: Into<TensorData>,
1884    {
1885        let data = data.into();
1886        check!(TensorCheck::creation_ops::<D>(
1887            "From Data",
1888            data.shape.as_slice()
1889        ));
1890        Self::new(K::from_data_dtype(data, device, dtype))
1891    }
1892
1893    /// Repeat the tensor along the given dimension.
1894    ///
1895    /// The output tensor has the same shape, except along the given dimension.
1896    ///
1897    /// # Arguments
1898    /// - `dim`: The dimension to repeat.
1899    /// - `times`: The number of times to repeat the tensor along the given dimension in the new tensor.
1900    ///
1901    /// # Returns
1902    ///
1903    /// A new tensor with the given dimension repeated `times` times.
1904    ///
1905    /// # Example
1906    ///
1907    /// ```rust
1908    /// use burn_tensor::backend::Backend;
1909    /// use burn_tensor::Tensor;
1910    ///
1911    /// fn example<B: Backend>() {
1912    ///     let device = Default::default();
1913    ///     // Create a 2D tensor with dimensions [3, 2]
1914    ///     let tensor = Tensor::<B, 2>::from_data([[3.0, 4.9], [2.0, 1.9], [4.0, 5.9]], &device);
1915    ///
1916    ///     // Repeat the tensor along the dimension 0 twice.
1917    ///     // [[3.0, 4.9], [2.0, 1.9], [4.0, 5.9], [3.0, 4.9], [2.0, 1.9], [4.0, 5.9]]
1918    ///     // The resulting tensor will have dimensions [6, 2].
1919    ///     let repeated = tensor.repeat_dim(0, 2);
1920    ///     println!("{repeated}");
1921    /// }
1922    /// ```
1923    pub fn repeat_dim(self, dim: usize, times: usize) -> Self {
1924        if times > 0 {
1925            Self::new(K::repeat_dim(self.primitive, dim, times))
1926        } else {
1927            let shape = self.shape().repeat(dim, times).unwrap();
1928            Self::empty(shape, &self.device())
1929        }
1930    }
1931
1932    /// Repeat the tensor along the given dimensions.
1933    /// # Arguments
1934    /// - `sizes`: Borrowed slice of the number of times to repeat each dimension.
1935    ///
1936    /// # Returns
1937    ///
1938    /// A new tensor with the given dimensions repeated `times` times.
1939    ///
1940    /// # Panics
1941    ///
1942    /// If `sizes` contains more elements than the number of dimensions.
1943    ///
1944    /// # Example
1945    ///
1946    /// ```rust
1947    ///
1948    /// use burn_tensor::backend::Backend;
1949    /// use burn_tensor::Tensor;
1950    ///
1951    /// fn example<B: Backend>() {
1952    ///     let device = Default::default();
1953    ///     // Create a 2D tensor with dimensions [3, 2]
1954    ///     let tensor = Tensor::<B, 2>::from_data([[3.0, 4.9], [2.0, 1.9], [4.0, 5.9]], &device);
1955    ///
1956    ///     // Repeat the tensor along the dimension 0 twice and the dimension 0 once.
1957    ///     // [[3.0, 4.9], [2.0, 1.9], [4.0, 5.9], [3.0, 4.9], [2.0, 1.9], [4.0, 5.9]]
1958    ///     // The resulting tensor will have dimensions [6, 2].
1959    ///     let repeated = tensor.repeat(&[2, 1]);
1960    /// }
1961    /// ```
1962    pub fn repeat(self, sizes: &[usize]) -> Self {
1963        if sizes.contains(&0) {
1964            let mut shape = self.shape();
1965            for (dim, &times) in sizes.iter().enumerate() {
1966                shape = shape.repeat(dim, times).unwrap();
1967            }
1968
1969            return Self::empty(shape, &self.device());
1970        }
1971
1972        let mut tensor = self;
1973        for (dim, &times) in sizes.iter().enumerate() {
1974            if times > 1 {
1975                tensor = tensor.repeat_dim(dim, times);
1976            }
1977        }
1978        tensor
1979    }
1980
1981    /// Applies element-wise equal comparison.
1982    ///
1983    /// # Returns
1984    /// A boolean tensor that is `true` where input is equal to `other` and `false` elsewhere.
1985    ///
1986    /// # Panics
1987    ///
1988    /// If the two tensors don't have the same shape.
1989    ///
1990    /// # Example
1991    ///
1992    /// ```rust
1993    /// use burn_tensor::backend::Backend;
1994    /// use burn_tensor::Tensor;
1995    ///
1996    /// fn example<B: Backend>() {
1997    ///     let device = Default::default();
1998    ///     let t1 = Tensor::<B, 2>::from_data([[2.0, 4.9], [2.0, 1.9], [4.0, 5.9]], &device);
1999    ///     let t2 = Tensor::<B, 2>::from_data([[3.0, 4.9], [2.0, 1.9], [4.0, 5.9]], &device);
2000    ///     // Compare the elements of the two 2D tensors with dimensions [3, 2].
2001    ///     // [[false, true], [true, true], [true, true]]
2002    ///     let equal = t1.equal(t2);
2003    ///     println!("{equal}");
2004    /// }
2005    /// ```
2006    pub fn equal(self, other: Self) -> Tensor<B, D, Bool> {
2007        check!(TensorCheck::binary_ops_ew("Equal", &self, &other));
2008        Tensor::new(K::equal(self.primitive, other.primitive))
2009    }
2010
2011    /// Applies element-wise non-equality comparison.
2012    ///
2013    /// # Returns
2014    /// A boolean tensor that is `true` where input is not equal to `other` and `false` elsewhere.
2015    ///
2016    /// # Panics
2017    ///
2018    /// If the two tensors don't have the same shape.
2019    ///
2020    /// # Example
2021    ///
2022    /// ```rust
2023    /// use burn_tensor::backend::Backend;
2024    /// use burn_tensor::Tensor;
2025    ///
2026    /// fn example<B: Backend>() {
2027    ///     let device = Default::default();
2028    ///     let t1 = Tensor::<B, 2>::from_data([[2.0, 4.9], [2.0, 1.9], [4.0, 5.9]], &device);
2029    ///     let t2 = Tensor::<B, 2>::from_data([[3.0, 4.9], [2.0, 1.9], [4.0, 5.9]], &device);
2030    ///     // Compare the elements of the two 2D tensors for inequality.
2031    ///     // [[true, false], [false, false], [false, false]]
2032    ///     let not_equal = t1.not_equal(t2);
2033    ///     println!("{not_equal}");
2034    /// }
2035    /// ```
2036    pub fn not_equal(self, other: Self) -> Tensor<B, D, Bool> {
2037        check!(TensorCheck::binary_ops_ew("NotEqual", &self, &other));
2038        Tensor::new(K::not_equal(self.primitive, other.primitive))
2039    }
2040
2041    /// Applies element wise equal comparison and returns a boolean tensor.
2042    ///
2043    /// # Arguments
2044    ///
2045    /// * `other` - The element to compare.
2046    ///
2047    /// # Example
2048    ///
2049    /// ```rust
2050    /// use burn_tensor::backend::Backend;
2051    /// use burn_tensor::{Tensor, Shape};
2052    ///
2053    /// fn example<B: Backend>() {
2054    ///    let device = B::Device::default();
2055    ///    let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
2056    ///    let tensor = tensor.equal_elem(3.0);
2057    ///    println!("{tensor}");
2058    ///    // [[false, false, true], [false, false, false]]
2059    /// }
2060    /// ```
2061    pub fn equal_elem<E: Element>(self, other: E) -> Tensor<B, D, Bool> {
2062        let other = Scalar::new(other, &self.dtype());
2063        Tensor::new(K::equal_elem(self.primitive, other))
2064    }
2065
2066    /// Applies element wise non-equality comparison and returns a boolean tensor.
2067    ///
2068    /// # Arguments
2069    ///
2070    /// * `other` - The element to compare.
2071    ///
2072    /// # Example
2073    ///
2074    /// ```rust
2075    /// use burn_tensor::backend::Backend;
2076    /// use burn_tensor::{Tensor, Shape};
2077    ///
2078    /// fn example<B: Backend>() {
2079    ///    let device = B::Device::default();
2080    ///    let tensor = Tensor::<B, 2>::from_data([[1.0, -2.0, 3.0], [5.0, 9.0, 6.0]], &device);
2081    ///    let tensor = tensor.not_equal_elem(3.0);
2082    ///    println!("{tensor}");
2083    ///    // [[true, true, false], [true, true, true]]
2084    /// }
2085    /// ```
2086    pub fn not_equal_elem<E: Element>(self, other: E) -> Tensor<B, D, Bool> {
2087        let other = Scalar::new(other, &self.dtype());
2088        Tensor::new(K::not_equal_elem(self.primitive, other))
2089    }
2090
2091    /// Concatenates all tensors into a new one along the given dimension.
2092    ///
2093    /// # Panics
2094    ///
2095    /// - If `dim` is higher than the rank.
2096    /// - If `tensors` is an empty vector.
2097    /// - If all tensors don't have the same shape (the dimension `dim` is ignored).
2098    ///
2099    /// # Example
2100    ///
2101    /// ```rust
2102    /// use burn_tensor::backend::Backend;
2103    /// use burn_tensor::Tensor;
2104    ///
2105    /// fn example<B: Backend>() {
2106    ///     let device = Default::default();
2107    ///     let t1 = Tensor::<B, 2>::from_data([[3.0, 4.9, 2.0, 1.0], [2.0, 1.9, 3.0, 1.0]], &device);
2108    ///     let t2 = Tensor::<B, 2>::from_data([[4.0, 5.9, 8.0], [1.4, 5.8, 6.0]], &device);
2109    ///
2110    ///     // Concatenate the two tensors with shapes [2, 4] and [2, 3] along the dimension 1.
2111    ///     // [[3.0, 4.9, 2.0, 1.0, 4.0, 5.9, 8.0], [2.0, 1.9, 3.0, 1.0, 1.4, 5.8, 6.0]]
2112    ///     // The resulting tensor will have shape [2, 7].
2113    ///     let concat = Tensor::cat(vec![t1, t2], 1);
2114    ///     println!("{concat}");
2115    /// }
2116    /// ```
2117    pub fn cat(tensors: Vec<Self>, dim: usize) -> Self {
2118        check!(TensorCheck::cat(&tensors, dim));
2119
2120        // Filter out tensors with size 0 along the concatenation dimension.
2121        // Empty tensors don't contribute to the output and would cause issues
2122        // in backend implementations (e.g., division by zero in slice_assign).
2123        // Safety: TensorCheck::cat ensures tensors is non-empty
2124        let first_tensor = tensors.first().unwrap();
2125        let device = first_tensor.device();
2126        let mut shape = first_tensor.shape();
2127
2128        let non_empty_primitives: Vec<_> = tensors
2129            .into_iter()
2130            .filter(|t| t.shape().dims[dim] > 0)
2131            .map(|t| t.primitive)
2132            .collect();
2133
2134        // If all tensors were empty, return an empty tensor with size 0 on concat dim
2135        if non_empty_primitives.is_empty() {
2136            shape.dims[dim] = 0;
2137            return Self::empty(shape, &device);
2138        }
2139
2140        Self::new(K::cat(non_empty_primitives, dim))
2141    }
2142
2143    /// Concatenates all tensors into a new one along a new dimension.
2144    ///
2145    /// # Panics
2146    ///
2147    /// - If all tensors don't have the same shape.
2148    /// - If given dimension is not with range of 0..D2
2149    ///
2150    /// # Example
2151    ///
2152    /// ```rust
2153    /// use burn_tensor::backend::Backend;
2154    /// use burn_tensor::Tensor;
2155    ///
2156    /// fn example<B: Backend>() {
2157    ///     let device = Default::default();
2158    ///     let t1 = Tensor::<B, 2>::from_data([[3.0, 4.9, 2.0], [2.0, 1.9, 3.0]], &device);
2159    ///     let t2 = Tensor::<B, 2>::from_data([[4.0, 5.9, 8.0], [1.4, 5.8, 6.0]], &device);
2160    ///     let t3 = Tensor::<B, 2>::from_data([[4.0, 5.9, 8.0], [1.4, 5.8, 6.0]], &device);
2161    ///
2162    ///     // Concatenate the three tensors with shape [2, 3] along a new dimension, 0.
2163    ///     // [[[3.0, 4.9, 2.0], [2.0, 1.9, 3.0]],
2164    ///     //  [[4.0, 5.9, 8.0], [1.4, 5.8, 6.0]],
2165    ///     //  [[4.0, 5.9, 8.0], [1.4, 5.8, 6.0]]]
2166    ///     // The resulting tensor will have shape [3, 2, 3].
2167    ///     let stacked= Tensor::stack::<3>(vec![t1, t2, t3], 0);
2168    ///     println!("{stacked}");
2169    /// }
2170    /// ```
2171    pub fn stack<const D2: usize>(tensors: Vec<Tensor<B, D, K>>, dim: usize) -> Tensor<B, D2, K> {
2172        check!(TensorCheck::stack::<B, D, K, D2>(&tensors, dim));
2173        let tensors = tensors.into_iter().map(|t| t.unsqueeze_dim(dim)).collect();
2174        Tensor::<B, D2, K>::cat(tensors, dim)
2175    }
2176
2177    /// Iterate over slices of tensors alongside a given dimension.
2178    ///
2179    /// # Panics
2180    ///
2181    /// If given dimension is greater than or equal to tensor rank.
2182    ///
2183    /// # Returns
2184    ///
2185    /// A tensor iterator.
2186    ///
2187    /// # Example
2188    ///
2189    /// ```rust
2190    /// use burn_tensor::backend::Backend;
2191    /// use burn_tensor::Tensor;
2192    /// fn example<B: Backend>() {
2193    ///   let device = Default::default();
2194    ///   let tensor = Tensor::<B,2>::from_data([[3.0, 4.9, 2.0], [2.0, 1.9, 3.0]], &device);
2195    ///   // Given a 2D tensor with dimensions [2, 3], iterate over slices of tensors along the dimension 0.
2196    ///   let iter = tensor.iter_dim(0);
2197    ///   for (i,tensor) in iter.enumerate() {
2198    ///     println!("Tensor {}: {}", i, tensor);
2199    ///     // Tensor 0: Tensor { data: [[3.0, 4.9, 2.0]], ... }
2200    ///     // Tensor 1: Tensor { data: [[2.0, 1.9, 3.0]], ... }
2201    ///  }
2202    /// }
2203    /// ```
2204    pub fn iter_dim(self, dim: usize) -> DimIter<B, D, K> {
2205        check!(TensorCheck::dim_ops::<D>("iter_dim", dim));
2206        DimIter::new(self, dim)
2207    }
2208
2209    /// Returns a new tensor with the given dimension narrowed to the given range.
2210    ///
2211    /// # Panics
2212    ///
2213    /// - If the dimension is greater than the number of dimensions of the tensor.
2214    /// - If the given range exceeds the number of elements on the given dimension.
2215    ///
2216    /// # Returns
2217    ///
2218    /// A new tensor with the given dimension narrowed to the given range.
2219    ///
2220    /// # Example
2221    ///
2222    /// ```rust
2223    /// use burn_tensor::backend::Backend;
2224    /// use burn_tensor::Tensor;
2225    ///
2226    /// fn example<B: Backend>() {
2227    ///     let device = Default::default();
2228    ///     // Create a 2D tensor with dimensions [4, 3]
2229    ///     let tensor = Tensor::<B, 2>::from_data(
2230    ///         [
2231    ///             [3.0, 4.9, 2.0],
2232    ///             [2.0, 1.9, 3.0],
2233    ///             [6.0, 1.5, 7.0],
2234    ///             [3.0, 4.9, 9.0],
2235    ///         ],
2236    ///         &device,
2237    ///     );
2238    ///     // Narrow the tensor along the dimension 0, keeping 3 elements starting from index 1.
2239    ///     // [[2.0, 1.9, 3.0], [6.0, 1.5, 7.0], [3.0, 4.9, 9.0]]
2240    ///     // The resulting tensor will have dimensions [3, 3].
2241    ///     let narrowed = tensor.narrow(0, 1, 3);
2242    ///     println!("{narrowed}");
2243    /// }
2244    /// ```
2245    pub fn narrow(self, dim: usize, start: usize, length: usize) -> Self {
2246        check!(TensorCheck::dim_ops::<D>("narrow", dim));
2247        check!(TensorCheck::narrow(&self, dim, start, length));
2248        let dims = self.dims();
2249
2250        let ranges: [Range<usize>; D] = dims
2251            .iter()
2252            .enumerate()
2253            .map(|(i, d)| {
2254                if i == dim {
2255                    start..(start + length)
2256                } else {
2257                    0..*d
2258                }
2259            })
2260            .collect::<Vec<_>>()
2261            .try_into()
2262            .unwrap();
2263
2264        Self::slice(self, ranges)
2265    }
2266
2267    /// Attempts to split the tensor into a specified number of chunks along a given dimension.
2268    /// May return less chunks than requested if the tensor size is not divisible by the number of chunks.
2269    ///
2270    /// When the given dimension is evenly divisible by the number of chunks, the chunks will be of equal size.
2271    /// Otherwise all chunks will be of equal size except for the last one.
2272    ///
2273    /// # Panics
2274    ///
2275    /// If the dimension is greater than the number of dimensions of the tensor.
2276    ///
2277    /// # Returns
2278    /// A vector of tensors.
2279    ///
2280    /// # Example
2281    ///
2282    /// ```rust
2283    /// use burn_tensor::backend::Backend;
2284    /// use burn_tensor::Tensor;
2285    ///
2286    /// fn example<B: Backend>() {
2287    ///     let device = Default::default();
2288    ///     // Create a 2D tensor with dimensions [4, 3]
2289    ///     let tensor = Tensor::<B, 2>::from_data(
2290    ///         [
2291    ///             [3.0, 4.9, 2.0],
2292    ///             [2.0, 1.9, 3.0],
2293    ///             [6.0, 1.5, 7.0],
2294    ///             [3.0, 4.9, 9.0],
2295    ///         ],
2296    ///         &device,
2297    ///     );
2298    ///     // Split the tensor along the dimension 1 into 2 chunks.
2299    ///     // The first chuck will have shape [4, 2]:
2300    ///     // [[3.0, 4.9], [2.0, 1.9], [6.0, 1.5], [3.0, 4.9]]
2301    ///     // The second chunk will have shape [4, 1]:
2302    ///     // [[2.0], [3.0], [7.0], [9.0]]
2303    ///     let chunks = tensor.chunk(2, 1);
2304    ///     println!("{chunks:?}");
2305    /// }
2306    /// ```
2307    pub fn chunk(self, chunks: usize, dim: usize) -> Vec<Self> {
2308        check!(TensorCheck::dim_ops::<D>("chunk", dim));
2309        let size = self.shape().dims[dim];
2310        if size < chunks {
2311            return (0..size)
2312                .map(|i| Self::narrow(self.clone(), dim, i, 1))
2313                .collect();
2314        }
2315
2316        let mut tensors = Vec::with_capacity(chunks);
2317        let mut sum_chunk_size = 0;
2318        if size.is_multiple_of(chunks) {
2319            let chunk_size = size / chunks;
2320            for _ in 0..chunks {
2321                tensors.push(Self::narrow(self.clone(), dim, sum_chunk_size, chunk_size));
2322                sum_chunk_size += chunk_size;
2323            }
2324        } else {
2325            let chunk_size = (size / chunks) + 1; // assumes not divisible
2326            for _ in 0..chunks - 1 {
2327                tensors.push(Self::narrow(self.clone(), dim, sum_chunk_size, chunk_size));
2328                sum_chunk_size += chunk_size;
2329            }
2330            let remainder = size % chunk_size;
2331            tensors.push(Self::narrow(self.clone(), dim, sum_chunk_size, remainder));
2332        }
2333
2334        tensors
2335    }
2336
2337    /// Splits the tensor into chunks of a specified size along a given dimension.
2338    /// Each chunk is a view of the original tensor.
2339    ///
2340    /// If the tensor size along the given dimension is not divisible by `split_size`,
2341    /// then the last chunk will be smaller.
2342    ///
2343    /// # Panics
2344    ///
2345    /// If the specified dimension to split along is greater than the number of dimensions of the tensor.
2346    ///
2347    /// # Returns
2348    ///
2349    /// A vector of tensors.
2350    ///
2351    /// # Example
2352    /// ```rust
2353    /// use burn_tensor::backend::Backend;
2354    /// use burn_tensor::Tensor;
2355    ///
2356    /// fn example<B: Backend>() {
2357    ///     let device = Default::default();
2358    ///     // Create a 1D tensor with 5 elements
2359    ///     let tensor = Tensor::<B, 1>::from_data([0.0, 1.0, 2.0, 3.0, 4.0], &device);
2360    ///     // Split the tensor into chunks of size 2 along dimension 0
2361    ///     let chunks = tensor.split(2, 0);
2362    ///     // The result is a vector of tensors:
2363    ///     // [Tensor([0.0, 1.0]), Tensor([2.0, 3.0]), Tensor([4.0])]
2364    ///     println!("{:?}", chunks);
2365    /// }
2366    /// ```
2367    pub fn split(self, split_size: usize, dim: usize) -> Vec<Self> {
2368        check!(TensorCheck::split::<D>(&self.shape(), split_size, dim));
2369        let size = self.shape().dims[dim];
2370        let mut tensors = Vec::new();
2371
2372        let mut start = 0;
2373        while start < size {
2374            let length = usize::min(split_size, size - start);
2375            tensors.push(Self::narrow(self.clone(), dim, start, length));
2376            start += length;
2377        }
2378
2379        tensors
2380    }
2381
2382    /// Splits the tensor into chunks with the specified sizes along a given dimension.
2383    /// Each chunk is a view of the original tensor.
2384    ///
2385    /// The sizes of the chunks are specified in the `split_sizes` vector. The sum of the sizes
2386    /// in `split_sizes` must equal the size of the tensor along the specified dimension.
2387    ///
2388    /// # Panics
2389    ///
2390    /// If the specified dimension to split along is greater than the number of dimensions of the tensor or
2391    /// if the sum of `dim_sizes` does not equal the size of the tensor along `dim`.
2392    ///
2393    /// # Returns
2394    ///
2395    /// A vector of tensors.
2396    ///
2397    /// # Example
2398    /// ```rust
2399    /// use burn_tensor::backend::Backend;
2400    /// use burn_tensor::Tensor;
2401    ///
2402    /// fn example<B: Backend>() {
2403    ///     let device = Default::default();
2404    ///     // Create a 1D tensor with 5 elements
2405    ///     let tensor = Tensor::<B, 1>::from_data([0.0, 1.0, 2.0, 3.0, 4.0], &device);
2406    ///     // Split the tensor into chunks with sizes [2, 3] along dimension 0
2407    ///     let chunks = tensor.split_with_sizes(vec![2, 3], 0);
2408    ///     // The result is a vector of tensors:
2409    ///     // [Tensor([0.0, 1.0]), Tensor([2.0, 3.0, 4.0])]
2410    ///     println!("{:?}", chunks);
2411    /// }
2412    /// ```
2413    pub fn split_with_sizes(self, split_sizes: Vec<usize>, dim: usize) -> Vec<Self> {
2414        check!(TensorCheck::split_with_sizes::<D>(
2415            &self.shape(),
2416            &split_sizes,
2417            dim
2418        ));
2419        let mut tensors = Vec::new();
2420
2421        let mut start = 0;
2422        for length in split_sizes {
2423            if length == 0 {
2424                continue;
2425            }
2426            tensors.push(Self::narrow(self.clone(), dim, start, length));
2427            start += length;
2428        }
2429
2430        tensors
2431    }
2432
2433    /// Tests if any element in the `tensor` evaluates to True.
2434    ///
2435    /// # Arguments
2436    ///
2437    /// * `tensor` - The tensor to test. All input tensor types (Float, Int, Bool) are supported.
2438    ///
2439    /// # Returns
2440    ///
2441    /// A boolean tensor `Tensor<B, 1, Bool>` containing a single element, True if any element in the input tensor
2442    /// evaluates to True, False otherwise.
2443    ///
2444    /// # Example
2445    ///
2446    /// ```rust
2447    /// use burn_tensor::backend::Backend;
2448    /// use burn_tensor::{Tensor, Bool};
2449    ///
2450    /// fn example<B: Backend>() {
2451    ///   let device = Default::default();
2452    ///   let tensor = Tensor::<B,2, Bool>::from_data([[true,false,true],[false,true,false]], &device);
2453    ///   let tensor_two = Tensor::<B,2, Bool>::from_data([[false,false,false],[false,false,false]], &device);
2454    ///
2455    ///   // Given a 2D tensor with dimensions [2, 3], test if any element in the tensor evaluates to True.
2456    ///   let any_tensor = tensor.any();
2457    ///   println!("{}", any_tensor);
2458    ///   // Tensor { data: [true], ... }
2459    ///
2460    ///   // Given a 2D tensor with dimensions [2, 3], test if any element in the tensor evaluates to True.
2461    ///   let any_tensor_two = tensor_two.any();
2462    ///   println!("{}", any_tensor_two);
2463    ///   // Tensor { data: [false], ... }
2464    /// }
2465    /// ```
2466    pub fn any(self) -> Tensor<B, 1, Bool> {
2467        Tensor::new(K::any(self.primitive))
2468    }
2469
2470    /// Tests if any element in the `tensor` evaluates to True along a given dimension `dim`.
2471    ///
2472    /// # Arguments
2473    ///
2474    /// * `tensor` - The tensor to test. All input tensor types (Float, Int, Bool) are supported.
2475    /// * `dim` - The axis along which to test.
2476    ///
2477    /// # Returns
2478    ///
2479    /// A boolean tensor `Tensor<B, D, Bool>` with the same shape as input `tensor`, except in the `dim` axis
2480    /// where the size is 1. The elem in the `dim` axis is True if any element along this dim in the input
2481    /// evaluates to True, False otherwise.
2482    ///
2483    /// # Example
2484    ///
2485    /// ```rust
2486    /// use burn_tensor::backend::Backend;
2487    /// use burn_tensor::{Tensor, Bool};
2488    ///
2489    /// fn example<B: Backend>() {
2490    ///     let device = Default::default();
2491    ///     let tensor =
2492    ///         Tensor::<B, 2, Bool>::from_data([[true, false, false], [false, true, false]], &device);
2493    ///     // Check if any element in the tensor evaluates to True along the dimension 1.
2494    ///     // [[true], [true]],
2495    ///     let any_dim = tensor.clone().any_dim(1);
2496    ///     println!("{any_dim}");
2497    /// }
2498    /// ```
2499    pub fn any_dim(self, dim: usize) -> Tensor<B, D, Bool> {
2500        Tensor::new(K::any_dim(self.primitive, dim))
2501    }
2502
2503    /// Tests if all elements in the `tensor` evaluate to True.
2504    ///
2505    /// # Arguments
2506    ///
2507    /// * `tensor` - The tensor to test. All input tensor types (Float, Int, Bool) are supported.
2508    ///
2509    /// # Returns
2510    ///
2511    /// A boolean tensor `Tensor<B, 1, Bool>` with a single element, True if all elements in the input tensor
2512    /// evaluate to True, False otherwise.
2513    ///
2514    /// # Example
2515    ///
2516    /// ```rust
2517    /// use burn_tensor::backend::Backend;
2518    /// use burn_tensor::{Tensor, Bool};
2519    ///
2520    /// fn example<B: Backend>() {
2521    ///     let device = Default::default();
2522    ///     let tensor =
2523    ///         Tensor::<B, 2, Bool>::from_data([[true, false, true], [true, true, true]], &device);
2524    ///     // Check if all elements in the tensor evaluate to True (which is not the case).
2525    ///     // [false]
2526    ///     let all = tensor.all();
2527    ///     println!("{all}");
2528    /// }
2529    /// ```
2530    pub fn all(self) -> Tensor<B, 1, Bool> {
2531        Tensor::new(K::all(self.primitive))
2532    }
2533
2534    /// Tests if all elements in the `tensor` evaluate to True along a given dimension `dim`.
2535    ///
2536    /// # Arguments
2537    ///
2538    /// * `tensor` - The tensor to test. All input tensor types (Float, Int, Bool) are supported.
2539    /// * `dim` - The axis along which to test.
2540    ///
2541    /// # Returns
2542    ///
2543    /// A boolean tensor `Tensor<B, D, Bool>` with the same shape as input `tensor`, except in the `dim` axis
2544    /// where the size is 1. The elem in the `dim` axis is True if all elements along this dim in the input
2545    /// evaluates to True, False otherwise.
2546    ///
2547    /// # Example
2548    ///
2549    /// ```rust
2550    /// use burn_tensor::backend::Backend;
2551    /// use burn_tensor::{Tensor, Bool};
2552    ///
2553    /// fn example<B: Backend>() {
2554    ///     let device = Default::default();
2555    ///     let tensor =
2556    ///         Tensor::<B, 2, Bool>::from_data([[true, true, false], [true, true, true]], &device);
2557    ///     // Check if all elements in the tensor evaluate to True along the dimension 1.
2558    ///     // [[true, true, false]]
2559    ///     let all_dim = tensor.clone().all_dim(0);
2560    ///     println!("{all_dim}");
2561    /// }
2562    /// ```
2563    pub fn all_dim(self, dim: usize) -> Tensor<B, D, Bool> {
2564        Tensor::new(K::all_dim(self.primitive, dim))
2565    }
2566
2567    /// Convert the tensor into a scalar.
2568    ///
2569    /// # Panics
2570    ///
2571    /// - If the tensor doesn't have one element.
2572    /// - If the backend fails to read the tensor data synchronously.
2573    ///
2574    /// # Returns
2575    ///
2576    /// The scalar value of the tensor.
2577    ///
2578    /// # Example
2579    ///
2580    /// ```rust
2581    /// use burn_tensor::backend::Backend;
2582    /// use burn_tensor::Tensor;
2583    ///
2584    /// fn example<B: Backend>() {
2585    ///     let device = Default::default();
2586    ///     let tensor = Tensor::<B, 2>::from_data([[3.0]], &device);
2587    ///     // Convert the tensor with a single element into a scalar.
2588    ///     let scalar = tensor.into_scalar();
2589    ///     println!("{scalar}");
2590    /// }
2591    /// ```
2592    pub fn into_scalar(self) -> K::Elem {
2593        crate::try_read_sync(self.into_scalar_async())
2594            .expect(
2595            "Failed to read tensor data synchronously. This can happen on platforms
2596            that don't support blocking futures like WASM. Try into_scalar_async instead.",
2597            )
2598            .expect("Error while reading data: use `try_into_scalar` instead to catch the error at runtime")
2599    }
2600
2601    /// Convert the tensor into a scalar and returns any error that might have occurred since the
2602    /// last time the device was synchronized.
2603    ///
2604    /// # Panics
2605    ///
2606    /// - If the tensor doesn't have one element.
2607    /// - If the backend fails to read the tensor data synchronously.
2608    ///
2609    /// # Returns
2610    ///
2611    /// The scalar value of the tensor.
2612    pub fn try_into_scalar(self) -> Result<K::Elem, ExecutionError> {
2613        crate::try_read_sync(self.into_scalar_async()).expect(
2614            "Failed to read tensor data synchronously. This can happen on platforms
2615            that don't support blocking futures like WASM. Try into_scalar_async instead.",
2616        )
2617    }
2618
2619    /// Convert the tensor into a scalar.
2620    ///
2621    /// # Panics
2622    ///
2623    /// If the tensor doesn't have one element.
2624    pub async fn into_scalar_async(self) -> Result<K::Elem, ExecutionError> {
2625        check!(TensorCheck::into_scalar::<D>(&self.shape()));
2626
2627        Ok(self.into_data_async().await?.iter().next().unwrap())
2628    }
2629
2630    /// Broadcast the tensor to the given shape.
2631    ///
2632    /// Only singleton dimensions can be expanded to a larger size. Other dimensions must have the same size
2633    /// (which can be inferred with `-1`).
2634    ///
2635    /// # Arguments
2636    ///
2637    /// * `shape` - The shape to broadcast the tensor to.
2638    ///   Can contain -1 for dimensions that should be inferred.
2639    ///   The number of elements in the shape must be greater or equal as
2640    ///   the number of dimensions of the tensor.
2641    ///
2642    /// # Panics
2643    ///
2644    /// If the tensor cannot be broadcasted to the given shape.
2645    ///
2646    /// # Returns
2647    ///
2648    /// A new tensor with the given shape.
2649    ///
2650    /// # Example
2651    ///
2652    /// ```rust
2653    /// use burn_tensor::backend::Backend;
2654    /// use burn_tensor::Tensor;
2655    ///
2656    /// fn example<B: Backend>() {
2657    ///     let device = Default::default();
2658    ///     // Create a 2D tensor with dimensions [3, 1]
2659    ///     let tensor = Tensor::<B, 2>::from_data([[1.], [2.], [3.]], &device);
2660    ///     // Expand the tensor to a new shape [3, 4]
2661    ///     // [[1.0, 1.0, 1.0, 1.0], [2.0, 2.0, 2.0, 2.0], [3.0, 3.0, 3.0, 3.0]]
2662    ///     let expanded = tensor.expand([3, 4]);
2663    ///     println!("{}", expanded);
2664    /// }
2665    /// ```
2666    pub fn expand<const D2: usize, S: BroadcastArgs<D, D2>>(self, shape: S) -> Tensor<B, D2, K> {
2667        let shape = shape.into_shape(&self.shape());
2668        check!(TensorCheck::expand::<D, D2>(
2669            "expand",
2670            &self.shape(),
2671            &shape,
2672        ));
2673
2674        Tensor::<B, D2, K>::new(K::expand(self.primitive, shape))
2675    }
2676
2677    /// Unfold windows along a dimension.
2678    ///
2679    /// Returns a view of the tensor with all complete windows of size `size` in dimension `dim`;
2680    /// where windows are advanced by `step` at each index.
2681    ///
2682    /// The number of windows is `max(0, (shape[dim] - size).ceil_div(step))`.
2683    ///
2684    /// The new view will have the unfolded dimension replaced by two dimensions;
2685    /// one in the position of the original dimension, with size equal to the number of windows,
2686    /// and one appended to the right-most position, with size equal to `size`.
2687    ///
2688    /// # Warning
2689    ///
2690    /// For the `ndarray` backend; this is not a view but a copy
2691    /// with duplicated data.
2692    ///
2693    /// # Arguments
2694    ///
2695    /// * `dim` - the dimension to unfold.
2696    /// * `size` - the size of each unfolded window.
2697    /// * `step` - the step between each window.
2698    ///
2699    /// # Returns
2700    ///
2701    /// A tensor view with the shape ``[pre=..., windows, post=..., size]``.
2702    pub fn unfold<const D2: usize, I: AsIndex>(
2703        self,
2704        dim: I,
2705        size: usize,
2706        step: usize,
2707    ) -> Tensor<B, D2, K> {
2708        let dim = dim.expect_dim_index(D);
2709        check!(TensorCheck::unfold::<D, D2>(
2710            "unfold",
2711            &self.shape(),
2712            dim,
2713            size,
2714            step,
2715        ));
2716        Tensor::<B, D2, K>::new(K::unfold(self.primitive, dim, size, step))
2717    }
2718}
2719
2720/// Iterator given by (Tensor::iter_dim).
2721pub struct DimIter<B, const D: usize, K>
2722where
2723    B: Backend,
2724    K: BasicOps<B>,
2725{
2726    start: usize,
2727    end: usize,
2728    dim: usize,
2729    ranges: [Range<usize>; D],
2730    tensor: Tensor<B, D, K>,
2731}
2732
2733impl<B: Backend, const D: usize, K: BasicOps<B>> Iterator for DimIter<B, D, K> {
2734    type Item = Tensor<B, D, K>;
2735
2736    fn next(&mut self) -> Option<Self::Item> {
2737        if self.start >= self.end {
2738            return None;
2739        }
2740
2741        let mut ranges = self.ranges.clone();
2742        ranges[self.dim] = self.start..(self.start + 1);
2743
2744        let slice = self.tensor.clone().slice(ranges);
2745        self.start += 1;
2746
2747        Some(slice)
2748    }
2749}
2750
2751impl<B: Backend, const D: usize, K: BasicOps<B>> DoubleEndedIterator for DimIter<B, D, K> {
2752    fn next_back(&mut self) -> Option<Self::Item> {
2753        if self.start >= self.end {
2754            return None;
2755        }
2756
2757        let mut ranges = self.ranges.clone();
2758        ranges[self.dim] = (self.end - 1)..self.end;
2759
2760        let slice = self.tensor.clone().slice(ranges);
2761        self.end = self.end.saturating_sub(1);
2762
2763        Some(slice)
2764    }
2765}
2766
2767impl<B: Backend, const D: usize, K: BasicOps<B>> DimIter<B, D, K> {
2768    fn new(tensor: Tensor<B, D, K>, dim: usize) -> Self {
2769        let dims = tensor.dims();
2770        let ranges = dims
2771            .iter()
2772            .map(|&dim| 0..dim)
2773            .collect::<Vec<Range<usize>>>();
2774        let ranges: [Range<usize>; D] = ranges.try_into().unwrap();
2775        Self {
2776            end: dims[dim],
2777            ranges,
2778            start: 0,
2779            dim,
2780            tensor,
2781        }
2782    }
2783}
2784
2785impl<B, const D: usize, K> Tensor<B, D, K>
2786where
2787    B: Backend,
2788    K: BasicOps<B>,
2789    <K as BasicOps<B>>::Elem: Debug,
2790{
2791    #[inline]
2792    fn push_newline_indent(acc: &mut String, indent: usize) {
2793        acc.push('\n');
2794        for _ in 0..indent {
2795            acc.push(' ');
2796        }
2797    }
2798    fn fmt_inner_tensor(
2799        &self,
2800        acc: &mut String,
2801        depth: usize,
2802        multi_index: &mut [usize],
2803        range: (usize, usize),
2804        precision: Option<usize>,
2805    ) {
2806        let (start, end) = range;
2807        for i in start..end {
2808            if i > 0 {
2809                acc.push_str(", ");
2810            }
2811            multi_index[depth] = i;
2812            let range: [Range<usize>; D] =
2813                core::array::from_fn(|i| multi_index[i]..multi_index[i] + 1);
2814
2815            let data = burn_std::reader::try_read_sync(self.clone().slice(range).into_data_async());
2816
2817            if let Some(Ok(data)) = data {
2818                let elem = data.iter::<<K as BasicOps<B>>::Elem>().next().unwrap();
2819                match (precision, K::name()) {
2820                    (Some(p), "Float") => acc.push_str(&format!("{elem:.p$}")),
2821                    (_, "Bool") => acc.push_str(&format!("{}", elem.to_bool())),
2822                    _ => acc.push_str(&format!("{elem:?}")),
2823                }
2824            } else {
2825                acc.push_str("<Tensor data not available>");
2826            }
2827        }
2828    }
2829
2830    fn fmt_outer_tensor(
2831        &self,
2832        acc: &mut String,
2833        depth: usize,
2834        multi_index: &mut [usize],
2835        print_options: &PrintOptions,
2836        summarize: bool,
2837        range: (usize, usize),
2838    ) {
2839        let (start, end) = range;
2840        for i in start..end {
2841            if i > start {
2842                acc.push(',');
2843                Self::push_newline_indent(acc, depth + 1);
2844            }
2845            acc.push('[');
2846            multi_index[depth] = i;
2847            self.display_recursive(acc, depth + 1, multi_index, print_options, summarize);
2848            acc.push(']');
2849        }
2850    }
2851
2852    /// Recursively formats the tensor data for display and appends it to the provided accumulator string.
2853    ///
2854    /// This function is designed to work with tensors of any dimensionality.
2855    /// It traverses the tensor dimensions recursively, converting the elements
2856    /// to strings and appending them to the accumulator string with the
2857    /// appropriate formatting.
2858    ///
2859    /// # Arguments
2860    ///
2861    /// * `acc` - A mutable reference to a `String` used as an accumulator for the formatted output.
2862    /// * `depth` - The current depth of the tensor dimensions being processed.
2863    /// * `multi_index` - A mutable slice of `usize` representing the current indices in each dimension.
2864    fn display_recursive(
2865        &self,
2866        acc: &mut String,
2867        depth: usize,
2868        multi_index: &mut [usize],
2869        print_options: &PrintOptions,
2870        summarize: bool,
2871    ) {
2872        let edge_items = print_options.edge_items;
2873
2874        if depth == 0 {
2875            acc.push('[');
2876        }
2877
2878        if depth == self.dims().len() - 1 {
2879            // if we are at the innermost dimension, just push its elements into the accumulator
2880            if summarize && self.dims()[depth] > 2 * edge_items {
2881                // print the starting `edge_items` elements
2882                self.fmt_inner_tensor(
2883                    acc,
2884                    depth,
2885                    multi_index,
2886                    (0, edge_items),
2887                    print_options.precision,
2888                );
2889                acc.push_str(", ...");
2890                // print the last `edge_items` elements
2891                self.fmt_inner_tensor(
2892                    acc,
2893                    depth,
2894                    multi_index,
2895                    (self.dims()[depth] - edge_items, self.dims()[depth]),
2896                    print_options.precision,
2897                );
2898            } else {
2899                // print all the elements
2900                self.fmt_inner_tensor(
2901                    acc,
2902                    depth,
2903                    multi_index,
2904                    (0, self.dims()[depth]),
2905                    print_options.precision,
2906                );
2907            }
2908        } else {
2909            // otherwise, iterate through the current dimension and recursively display the inner tensors
2910            if summarize && self.dims()[depth] > 2 * edge_items {
2911                self.fmt_outer_tensor(
2912                    acc,
2913                    depth,
2914                    multi_index,
2915                    print_options,
2916                    summarize,
2917                    (0, edge_items),
2918                );
2919
2920                acc.push(',');
2921                Self::push_newline_indent(acc, depth + 1);
2922                acc.push_str("...");
2923                Self::push_newline_indent(acc, depth + 1);
2924
2925                self.fmt_outer_tensor(
2926                    acc,
2927                    depth,
2928                    multi_index,
2929                    print_options,
2930                    summarize,
2931                    (self.dims()[depth] - edge_items, self.dims()[depth]),
2932                );
2933            } else {
2934                self.fmt_outer_tensor(
2935                    acc,
2936                    depth,
2937                    multi_index,
2938                    print_options,
2939                    summarize,
2940                    (0, self.dims()[depth]),
2941                );
2942            }
2943        }
2944
2945        if depth == 0 {
2946            acc.push(']');
2947        }
2948    }
2949}
2950
2951#[derive(Clone, Debug)]
2952/// Options for Tensor pretty printing
2953pub struct PrintOptions {
2954    /// number of elements to start summarizing tensor
2955    pub threshold: usize,
2956
2957    /// number of starting elements and ending elements to display
2958    pub edge_items: usize,
2959
2960    /// Precision for floating point numbers
2961    pub precision: Option<usize>,
2962}
2963
2964static PRINT_OPTS: RwLock<PrintOptions> = RwLock::new(PrintOptions::const_default());
2965
2966impl PrintOptions {
2967    /// Print options with default values
2968    pub const fn const_default() -> Self {
2969        Self {
2970            threshold: 1000,
2971            edge_items: 3,
2972            precision: None,
2973        }
2974    }
2975}
2976
2977impl Default for PrintOptions {
2978    fn default() -> Self {
2979        Self::const_default()
2980    }
2981}
2982
2983/// Set print options
2984pub fn set_print_options(options: PrintOptions) {
2985    let mut print_opts = PRINT_OPTS.write().unwrap();
2986    *print_opts = options;
2987}
2988
2989/// Pretty print tensors
2990impl<B, const D: usize, K> core::fmt::Display for Tensor<B, D, K>
2991where
2992    B: Backend,
2993    B::IntElem: core::fmt::Display,
2994    K: BasicOps<B>,
2995    <K as BasicOps<B>>::Elem: Debug,
2996{
2997    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
2998        writeln!(f, "Tensor {{")?;
2999
3000        {
3001            // Do not lock the mutex for the whole function
3002            let mut po = { PRINT_OPTS.read().unwrap().clone() };
3003
3004            // Override the precision if it is set from the formatter
3005            // This will be possible when the tensor is printed using the `{:.*}` syntax
3006            if let Some(precision) = f.precision() {
3007                po.precision = Some(precision);
3008            }
3009
3010            let mut acc = String::new();
3011            let mut multi_index = vec![0; D];
3012            let summarize = self.shape().num_elements() > po.threshold;
3013
3014            self.display_recursive(&mut acc, 0, &mut multi_index, &po, summarize);
3015
3016            writeln!(f, "  data:")?;
3017            write!(f, "{acc}")?;
3018            writeln!(f, ",")?;
3019        }
3020
3021        writeln!(f, "  shape:  {:?},", self.dims())?;
3022        writeln!(f, "  device:  {:?},", self.device())?;
3023        writeln!(f, "  backend:  {:?},", B::name(&self.device()))?;
3024        writeln!(f, "  kind:  {:?},", K::name())?;
3025
3026        let dtype = self.primitive.dtype();
3027
3028        writeln!(f, "  dtype:  {:?},", dtype.name())?;
3029        write!(f, "}}")
3030    }
3031}
3032
3033/// Trait used for movedim arguments
3034pub trait MovedimArgs {
3035    /// Converts into a set of dimensions `Vec<usize>` for the `tensor.movedim()` function
3036    fn into_dim_vec<const D: usize>(self) -> Vec<usize>;
3037}
3038
3039impl MovedimArgs for Vec<i32> {
3040    fn into_dim_vec<const D: usize>(self) -> Vec<usize> {
3041        let set = self
3042            .iter()
3043            .map(|&dim| {
3044                if dim < 0 {
3045                    (D as i32 + dim) as usize
3046                } else {
3047                    dim as usize
3048                }
3049            })
3050            .collect::<Vec<usize>>();
3051        check!(TensorCheck::movedim_args_vec::<D>(&set));
3052
3053        set
3054    }
3055}
3056
3057impl MovedimArgs for Vec<usize> {
3058    fn into_dim_vec<const D: usize>(self) -> Vec<usize> {
3059        check!(TensorCheck::movedim_args_vec::<D>(&self));
3060        self
3061    }
3062}
3063
3064impl MovedimArgs for usize {
3065    #[allow(clippy::vec_init_then_push)]
3066    fn into_dim_vec<const D: usize>(self) -> Vec<usize> {
3067        check!(TensorCheck::movedim_args_usize::<D>(self));
3068
3069        let mut set = Vec::with_capacity(1);
3070        set.push(self);
3071
3072        set
3073    }
3074}
3075
3076impl MovedimArgs for i32 {
3077    #[allow(clippy::vec_init_then_push)]
3078    fn into_dim_vec<const D: usize>(self) -> Vec<usize> {
3079        check!(TensorCheck::movedim_args_i32::<D>(self));
3080
3081        let dim = if self < 0 {
3082            (D as i32 + self) as usize
3083        } else {
3084            self as usize
3085        };
3086
3087        let mut set = Vec::with_capacity(1);
3088        set.push(dim);
3089
3090        set
3091    }
3092}
3093
3094/// Trait used for reshape arguments.
3095pub trait ReshapeArgs<const D2: usize>: Debug {
3096    /// Converts to a shape.
3097    fn into_shape<const D: usize>(self, source: Shape) -> Shape;
3098}
3099
3100impl<const D2: usize, I: AsIndex> ReshapeArgs<D2> for [I; D2] {
3101    fn into_shape<const D: usize>(self, source: Shape) -> Shape {
3102        unwrap_shape_reshape(source.reshape(self))
3103    }
3104}
3105
3106impl<const D2: usize> ReshapeArgs<D2> for Shape {
3107    fn into_shape<const D: usize>(self, source: Shape) -> Shape {
3108        unwrap_shape_reshape(source.reshape(self))
3109    }
3110}
3111
3112/// Trait used for broadcast arguments.
3113pub trait BroadcastArgs<const D1: usize, const D2: usize> {
3114    /// Converts to a shape.
3115    fn into_shape(self, shape: &Shape) -> Shape;
3116}
3117
3118impl<const D1: usize, const D2: usize> BroadcastArgs<D1, D2> for Shape {
3119    fn into_shape(self, _shape: &Shape) -> Shape {
3120        self
3121    }
3122}
3123
3124impl<const D1: usize, const D2: usize, E: AsIndex> BroadcastArgs<D1, D2> for [E; D2] {
3125    // Passing -1 as the size for a dimension means not changing the size of that dimension.
3126    fn into_shape(self, shape: &Shape) -> Shape {
3127        if self.len() < shape.num_dims() {
3128            panic!("Broadcast arguments must be greater than the number of dimensions");
3129        }
3130
3131        // Zip the two shapes in reverse order and replace -1 with the actual dimension value.
3132        let new_shape: Vec<_> = self
3133            .iter()
3134            .rev()
3135            .map(|x| {
3136                let primitive = x.as_index();
3137                if primitive < -1 || primitive == 0 {
3138                    panic!("Broadcast arguments must be positive or -1");
3139                }
3140                primitive
3141            })
3142            .zip(shape.iter().rev().chain(repeat(&0)).take(self.len())) // Pad the original shape with 0s
3143            .map(|(x, &y)| if x == -1 { y } else { x as usize })
3144            .collect::<Vec<_>>()
3145            .into_iter()
3146            .rev()
3147            .collect();
3148
3149        if new_shape.contains(&0) {
3150            panic!("Cannot substitute -1 for a non-existing dimension");
3151        }
3152
3153        let new_shape: [usize; D2] = new_shape.try_into().unwrap();
3154
3155        Shape::from(new_shape)
3156    }
3157}
3158
3159impl<B, const D: usize, K> Serialize for Tensor<B, D, K>
3160where
3161    B: Backend,
3162    K: BasicOps<B>,
3163    K::Elem: Debug + Copy + Serialize,
3164{
3165    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
3166        let data = self.to_data();
3167        data.serialize(serializer)
3168    }
3169}
3170
3171impl<'de, B, const D: usize, K> Deserialize<'de> for Tensor<B, D, K>
3172where
3173    B: Backend,
3174    K: BasicOps<B>,
3175    K::Elem: Debug + Copy + Deserialize<'de>,
3176{
3177    fn deserialize<De: Deserializer<'de>>(deserializer: De) -> Result<Self, De::Error> {
3178        let tensor = Tensor::from_data(
3179            TensorData::deserialize(deserializer)?,
3180            &<B::Device as Default>::default(),
3181        );
3182        Ok(tensor)
3183    }
3184}
3185
3186#[cfg(test)]
3187mod tests {
3188    use crate::{Shape, s};
3189
3190    #[test]
3191    fn slice_range_single_dim_leading() {
3192        let shape = Shape::new([8, 4]);
3193
3194        // Half-open range
3195        let slices = shape.clone().into_slices([0..5]);
3196        assert_eq!(slices[0].to_range(8), 0..5);
3197        let slices = shape.clone().into_slices([-3..-1]);
3198        assert_eq!(slices[0].to_range(8), 5..7);
3199
3200        // Inclusive range
3201        let slices = shape.clone().into_slices([0..=4]);
3202        assert_eq!(slices[0].to_range(8), 0..5);
3203        let slices = shape.clone().into_slices([-2..=-1]);
3204        assert_eq!(slices[0].to_range(8), 6..8);
3205
3206        // Unbounded start
3207        let slices = shape.clone().into_slices([..3]);
3208        assert_eq!(slices[0].to_range(8), 0..3);
3209        let slices = shape.clone().into_slices([..-5]);
3210        assert_eq!(slices[0].to_range(8), 0..3);
3211
3212        // Unbounded end
3213        let slices = shape.clone().into_slices([5..]);
3214        assert_eq!(slices[0].to_range(8), 5..8);
3215        let slices = shape.clone().into_slices([-3..]);
3216        assert_eq!(slices[0].to_range(8), 5..8);
3217
3218        // Full range
3219        let slices = shape.into_slices([..]);
3220        assert_eq!(slices[0].to_range(8), 0..8);
3221    }
3222
3223    #[test]
3224    fn test_negative_slice_indices() {
3225        use crate::Slice;
3226
3227        // Test negative indices conversion
3228        let slice: Slice = (-3..-1).into();
3229        assert_eq!(slice.start, -3);
3230        assert_eq!(slice.end, Some(-1));
3231
3232        // Test to_range conversion with size 8
3233        let range = slice.to_range(8);
3234        assert_eq!(range, 5..7);
3235
3236        // Test with shape slice
3237        let shape = Shape::new([8, 4]);
3238        let result = shape.clone().into_slices([-3..-1]);
3239        assert_eq!(result[0].to_range(8), 5..7);
3240
3241        // Test more negative index cases
3242        let slice2: Slice = (-5..).into();
3243        assert_eq!(slice2.to_range(10), 5..10);
3244
3245        let slice3: Slice = (..-2).into();
3246        assert_eq!(slice3.to_range(10), 0..8);
3247
3248        // Test with s! macro - single dimension returns Slice directly
3249        let slice4 = s![-3..-1];
3250        assert_eq!(slice4.start, -3);
3251        assert_eq!(slice4.end, Some(-1));
3252    }
3253
3254    #[test]
3255    fn slice_range_multi_dim() {
3256        let shape = Shape::new([8, 4]);
3257
3258        // Multiple ways to provide ranges
3259        let slices = shape.clone().into_slices([0..5, 0..4]);
3260        assert_eq!(slices[0].to_range(8), 0..5);
3261        assert_eq!(slices[1].to_range(4), 0..4);
3262
3263        let slices = shape.clone().into_slices([0.., 0..]);
3264        assert_eq!(slices[0].to_range(8), 0..8);
3265        assert_eq!(slices[1].to_range(4), 0..4);
3266
3267        let slices = shape.clone().into_slices([0..=7, 0..=3]);
3268        assert_eq!(slices[0].to_range(8), 0..8);
3269        assert_eq!(slices[1].to_range(4), 0..4);
3270
3271        let slices = shape.clone().into_slices([0..5, 0..3]);
3272        assert_eq!(slices[0].to_range(8), 0..5);
3273        assert_eq!(slices[1].to_range(4), 0..3);
3274
3275        let slices = shape.into_slices([0.., 0..]);
3276        assert_eq!(slices[0].to_range(8), 0..8);
3277        assert_eq!(slices[1].to_range(4), 0..4);
3278    }
3279
3280    #[test]
3281    fn slice_range_multi_dim_index() {
3282        let shape = Shape::new([8, 4]);
3283
3284        // Indices (single integer) should also convert to correct range
3285        let slices = shape.clone().into_slices([0, 2]);
3286        assert_eq!(slices[0].to_range(8), 0..1);
3287        assert_eq!(slices[1].to_range(4), 2..3);
3288
3289        let slices = shape.into_slices([-1, -1]);
3290        assert_eq!(slices[0].to_range(8), 7..8);
3291        assert_eq!(slices[1].to_range(4), 3..4);
3292    }
3293
3294    #[test]
3295    fn slice_range_multi_dim_heterogeneous() {
3296        // Slice macro `s![]` can be used to provide different range types
3297        let shape = Shape::new([8, 4, 2]);
3298        let slice = s![0..5, .., -1];
3299        let slices = shape.into_slices(slice);
3300        assert_eq!(slices[0].to_range(8), 0..5);
3301        assert_eq!(slices[1].to_range(4), 0..4);
3302        assert_eq!(slices[2].to_range(2), 1..2);
3303
3304        let shape = Shape::new([8, 4, 2, 3]);
3305        let slice = s![..=4, 0..=3, .., -2..];
3306        let slices = shape.into_slices(slice);
3307        assert_eq!(slices[0].to_range(8), 0..5);
3308        assert_eq!(slices[1].to_range(4), 0..4);
3309        assert_eq!(slices[2].to_range(2), 0..2);
3310        assert_eq!(slices[3].to_range(3), 1..3);
3311
3312        let shape = Shape::new([3, 4]);
3313        let slice = s![1..-1, ..];
3314        let slices = shape.into_slices(slice);
3315        assert_eq!(slices[0].to_range(3), 1..2);
3316        assert_eq!(slices[1].to_range(4), 0..4);
3317    }
3318}