Struct numpy::array::PyArray[][src]

pub struct PyArray<T, D>(_, _, _);
Expand description

A safe, static-typed interface for NumPy ndarray.

Memory location

These methods don’t allocate memory and use Box<[T]> as a internal buffer.

Please take care that you cannot use some destructive methods like resize, for this kind of array.

These methods allocate memory in Python’s private heap.

In both cases, PyArray is managed by Python GC. So you can neither retrieve it nor deallocate it manually.

Reference

Like new, all constractor methods of PyArray returns &PyArray.

This design follows pyo3’s ownership concept.

Data type and Dimension

PyArray has 2 type parametes T and D. T represents its data type like f32, and D represents its dimension.

All data types you can use implements Element.

Dimensions are represented by ndarray’s Dimension trait.

Typically, you can use Ix1, Ix2, .. for fixed size arrays, and use IxDyn for dynamic dimensioned arrays. They’re re-exported from ndarray crate.

You can also use various type aliases we provide, like PyArray1 or PyArrayDyn.

To specify concrete dimension like 3×4×5, you can use types which implements ndarray’s IntoDimension trait. Typically, you can use array(e.g. [3, 4, 5]) or tuple(e.g. (3, 4, 5)) as a dimension.

Example

use numpy::PyArray;
use ndarray::Array;
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::arange(py, 0., 4., 1.).reshape([2, 2]).unwrap();
    let array = array![[3., 4.], [5., 6.]];
    assert_eq!(
        array.dot(&pyarray.readonly().as_array()),
        array![[8., 15.], [12., 23.]]
    );
});

Implementations

Gets a raw PyArrayObject pointer.

Returns dtype of the array. Counterpart of array.dtype in Python.

Example

pyo3::Python::with_gil(|py| {
   let array = numpy::PyArray::from_vec(py, vec![1, 2, 3i32]);
   let dtype = array.dtype();
   assert_eq!(dtype.get_datatype().unwrap(), numpy::DataType::Int32);
});

Returns a temporally unwriteable reference of the array.

Returns true if the internal data of the array is C-style contiguous (default of numpy and ndarray) or Fortran-style contiguous.

Example

use pyo3::types::IntoPyDict;
pyo3::Python::with_gil(|py| {
    let array = numpy::PyArray::arange(py, 0, 10, 1);
    assert!(array.is_contiguous());
    let locals = [("np", numpy::get_array_module(py).unwrap())].into_py_dict(py);
    let not_contiguous: &numpy::PyArray1<f32> = py
        .eval("np.zeros((3, 5))[::2, 4]", Some(locals), None)
        .unwrap()
        .downcast()
        .unwrap();
    assert!(!not_contiguous.is_contiguous());
});

Returns true if the internal data of the array is Fortran-style contiguous.

Returns true if the internal data of the array is C-style contiguous.

Get Py<PyArray> from &PyArray, which is the owned wrapper of PyObject.

You can use this method when you have to avoid lifetime annotation to your function args or return types, like used with pyo3’s pymethod.

Example

use numpy::PyArray1;
fn return_py_array() -> pyo3::Py<PyArray1<i32>> {
   pyo3::Python::with_gil(|py| PyArray1::zeros(py, [5], false).to_owned())
}
let array = return_py_array();
pyo3::Python::with_gil(|py| {
    assert_eq!(array.as_ref(py).readonly().as_slice().unwrap(), &[0, 0, 0, 0, 0]);
});

Constructs PyArray from raw python object without incrementing reference counts.

Constructs PyArray from raw python object and increments reference counts.

Returns the number of dimensions in the array.

Same as numpy.ndarray.ndim

Example

use numpy::PyArray3;
pyo3::Python::with_gil(|py| {
    let arr = PyArray3::<f64>::new(py, [4, 5, 6], false);
    assert_eq!(arr.ndim(), 3);
});

Returns a slice which contains how many bytes you need to jump to the next row.

Same as numpy.ndarray.strides

Example

use numpy::PyArray3;
pyo3::Python::with_gil(|py| {
    let arr = PyArray3::<f64>::new(py, [4, 5, 6], false);
    assert_eq!(arr.strides(), &[240, 48, 8]);
});

Returns a slice which contains dimmensions of the array.

Same as numpy.ndarray.shape

Example

use numpy::PyArray3;
pyo3::Python::with_gil(|py| {
    let arr = PyArray3::<f64>::new(py, [4, 5, 6], false);
    assert_eq!(arr.shape(), &[4, 5, 6]);
});

Calcurates the total number of elements in the array.

Same as shape, but returns D

Creates a new uninitialized PyArray in python heap.

If is_fortran == true, returns Fortran-order array. Else, returns C-order array.

Example

use numpy::PyArray3;
pyo3::Python::with_gil(|py| {
    let arr = PyArray3::<i32>::new(py, [4, 5, 6], false);
    assert_eq!(arr.shape(), &[4, 5, 6]);
});

Construct a new nd-dimensional array filled with 0.

If is_fortran is true, then a fortran order array is created, otherwise a C-order array is created.

See also PyArray_Zeros

Example

use numpy::PyArray2;
pyo3::Python::with_gil(|py| {
    let pyarray: &PyArray2<usize> = PyArray2::zeros(py, [2, 2], false);
    assert_eq!(pyarray.readonly().as_array(), array![[0, 0], [0, 0]]);
});

Returns the immutable view of the internal data of PyArray as slice.

Please consider the use of safe alternatives (PyReadonlyArray::as_slice , as_cell_slice or to_vec) instead of this.

Safety

If the internal array is not readonly and can be mutated from Python code, holding the slice might cause undefined behavior.

Returns the view of the internal data of PyArray as &[Cell<T>].

Returns the view of the internal data of PyArray as mutable slice.

Safety

If another reference to the internal data exists(e.g., &[T] or ArrayView), it might cause undefined behavior.

In such case, please consider the use of as_cell_slice,

Construct PyArray from ndarray::Array.

This method uses internal Vec of ndarray::Array as numpy array.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::from_owned_array(py, array![[1, 2], [3, 4]]);
    assert_eq!(pyarray.readonly().as_array(), array![[1, 2], [3, 4]]);
});

Get the immutable reference of the specified element, with checking the passed index is valid.

Please consider the use of safe alternatives (PyReadonlyArray::get or get_owned) instead of this.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let arr = PyArray::arange(py, 0, 16, 1).reshape([2, 2, 4]).unwrap();
    assert_eq!(*unsafe { arr.get([1, 0, 3]) }.unwrap(), 11);
});

Safety

If the internal array is not readonly and can be mutated from Python code, holding the slice might cause undefined behavior.

Get the immutable reference of the specified element, without checking the passed index is valid.

See NpyIndex for what types you can use as index.

Passing an invalid index can cause undefined behavior(mostly SIGSEGV).

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let arr = PyArray::arange(py, 0, 16, 1).reshape([2, 2, 4]).unwrap();
    assert_eq!(unsafe { *arr.uget([1, 0, 3]) }, 11);
});

Same as uget, but returns &mut T.

Get dynamic dimensioned array from fixed dimension array.

Get the copy of the specified element in the array.

See NpyIndex for what types you can use as index.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let arr = PyArray::arange(py, 0, 16, 1).reshape([2, 2, 4]).unwrap();
    assert_eq!(arr.get_owned([1, 0, 3]), Some(11));
});

Returns the copy of the internal data of PyArray to Vec.

Returns ErrorKind::NotContiguous if the internal array is not contiguous. See also as_slice

Example

use numpy::PyArray2;
use pyo3::types::IntoPyDict;
pyo3::Python::with_gil(|py| {
    let locals = [("np", numpy::get_array_module(py).unwrap())].into_py_dict(py);
    let array: &PyArray2<i64> = py
        .eval("np.array([[0, 1], [2, 3]], dtype='int64')", Some(locals), None)
        .unwrap()
        .downcast()
        .unwrap();
    assert_eq!(array.to_vec().unwrap(), vec![0, 1, 2, 3]);
});

Construct PyArray from ndarray::ArrayBase.

This method allocates memory in Python’s heap via numpy api, and then copies all elements of the array there.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::from_array(py, &array![[1, 2], [3, 4]]);
    assert_eq!(pyarray.readonly().as_array(), array![[1, 2], [3, 4]]);
});

Get the immutable view of the internal data of PyArray, as ndarray::ArrayView.

Please consider the use of safe alternatives (PyReadonlyArray::as_array or to_array) instead of this.

Safety

If the internal array is not readonly and can be mutated from Python code, holding the ArrayView might cause undefined behavior.

Returns the internal array as ArrayViewMut. See also as_array.

Safety

If another reference to the internal data exists(e.g., &[T] or ArrayView), it might cause undefined behavior.

Get a copy of PyArray as ndarray::Array.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let py_array = PyArray::arange(py, 0, 4, 1).reshape([2, 2]).unwrap();
    assert_eq!(
        py_array.to_owned_array(),
        array![[0, 1], [2, 3]]
    )
});

Get the element of zero-dimensional PyArray.

See inner for example.

Construct one-dimension PyArray from slice.

Example

use numpy::PyArray;
let array = [1, 2, 3, 4, 5];
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::from_slice(py, &array);
    assert_eq!(pyarray.readonly().as_slice().unwrap(), &[1, 2, 3, 4, 5]);
});

Construct one-dimension PyArray from Vec.

Example

use numpy::PyArray;
let vec = vec![1, 2, 3, 4, 5];
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::from_vec(py, vec);
    assert_eq!(pyarray.readonly().as_slice().unwrap(), &[1, 2, 3, 4, 5]);
});

Construct one-dimension PyArray from a type which implements ExactSizeIterator.

Example

use numpy::PyArray;
use std::collections::BTreeSet;
let vec = vec![1, 2, 3, 4, 5];
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::from_exact_iter(py, vec.iter().map(|&x| x));
    assert_eq!(pyarray.readonly().as_slice().unwrap(), &[1, 2, 3, 4, 5]);
});

Construct one-dimension PyArray from a type which implements IntoIterator.

If no reliable size_hint is available, this method can allocate memory multiple time, which can hurt performance.

Example

use numpy::PyArray;
let set: std::collections::BTreeSet<u32> = [4, 3, 2, 5, 1].into_iter().cloned().collect();
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::from_iter(py, set);
    assert_eq!(pyarray.readonly().as_slice().unwrap(), &[1, 2, 3, 4, 5]);
});

Extends or trancates the length of 1 dimension PyArray.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::arange(py, 0, 10, 1);
    assert_eq!(pyarray.len(), 10);
    pyarray.resize(100).unwrap();
    assert_eq!(pyarray.len(), 100);
});

Iterates all elements of this array. See NpySingleIter for more.

Construct a two-dimension PyArray from Vec<Vec<T>>.

This function checks all dimension of inner vec, and if there’s any vec where its dimension differs from others, it returns ArrayCastError.

Example

use numpy::PyArray;
let vec2 = vec![vec![1, 2, 3]; 2];
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::from_vec2(py, &vec2).unwrap();
    assert_eq!(pyarray.readonly().as_array(), array![[1, 2, 3], [1, 2, 3]]);
    assert!(PyArray::from_vec2(py, &[vec![1], vec![2, 3]]).is_err());
});

Construct a three-dimension PyArray from Vec<Vec<Vec<T>>>.

This function checks all dimension of inner vec, and if there’s any vec where its dimension differs from others, it returns error.

Example

use numpy::PyArray;
let vec3 = vec![vec![vec![1, 2]; 2]; 2];
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::from_vec3(py, &vec3).unwrap();
    assert_eq!(
        pyarray.readonly().as_array(),
        array![[[1, 2], [1, 2]], [[1, 2], [1, 2]]]
    );
    assert!(PyArray::from_vec3(py, &[vec![vec![1], vec![]]]).is_err());
});

Copies self into other, performing a data-type conversion if necessary.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let pyarray_f = PyArray::arange(py, 2.0, 5.0, 1.0);
    let pyarray_i = PyArray::<i64, _>::new(py, [3], false);
    assert!(pyarray_f.copy_to(pyarray_i).is_ok());
    assert_eq!(pyarray_i.readonly().as_slice().unwrap(), &[2, 3, 4]);
});

Cast the PyArray<T> to PyArray<U>, by allocating a new array.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let pyarray_f = PyArray::arange(py, 2.0, 5.0, 1.0);
    let pyarray_i = pyarray_f.cast::<i32>(false).unwrap();
    assert!(pyarray_f.copy_to(pyarray_i).is_ok());
    assert_eq!(pyarray_i.readonly().as_slice().unwrap(), &[2, 3, 4]);
});

Construct a new array which has same values as self, same matrix order, but has different dimensions specified by dims.

Since a returned array can contain a same pointer as self, we highly recommend to drop an old array, if this method returns Ok.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let array = PyArray::from_exact_iter(py, 0..9);
    let array = array.reshape([3, 3]).unwrap();
    assert_eq!(array.readonly().as_array(), array![[0, 1, 2], [3, 4, 5], [6, 7, 8]]);
    assert!(array.reshape([5]).is_err());
});

Same as reshape, but you can change the order of returned matrix.

Return evenly spaced values within a given interval. Same as numpy.arange.

See also PyArray_Arange.

Example

use numpy::PyArray;
pyo3::Python::with_gil(|py| {
    let pyarray = PyArray::arange(py, 2.0, 4.0, 0.5);
    assert_eq!(pyarray.readonly().as_slice().unwrap(), &[2.0, 2.5, 3.0, 3.5]);
    let pyarray = PyArray::arange(py, -2, 4, 3);
    assert_eq!(pyarray.readonly().as_slice().unwrap(), &[-2, 1]);
});

Methods from Deref<Target = PyAny>

Convert this PyAny to a concrete Python type.

Determines whether this object has the given attribute.

This is equivalent to the Python expression hasattr(self, attr_name).

Retrieves an attribute value.

This is equivalent to the Python expression self.attr_name.

Sets an attribute value.

This is equivalent to the Python expression self.attr_name = value.

Deletes an attribute.

This is equivalent to the Python expression del self.attr_name.

Compares two Python objects.

This is equivalent to:

if self == other:
    return Equal
elif a < b:
    return Less
elif a > b:
    return Greater
else:
    raise TypeError("PyAny::compare(): All comparisons returned false")

Compares two Python objects.

Depending on the value of compare_op, this is equivalent to one of the following Python expressions:

  • CompareOp::Eq: self == other
  • CompareOp::Ne: self != other
  • CompareOp::Lt: self < other
  • CompareOp::Le: self <= other
  • CompareOp::Gt: self > other
  • CompareOp::Ge: self >= other

Determines whether this object is callable.

Calls the object.

This is equivalent to the Python expression self(*args, **kwargs).

Calls the object without arguments.

This is equivalent to the Python expression self().

Calls the object with only positional arguments.

This is equivalent to the Python expression self(*args).

Calls a method on the object.

This is equivalent to the Python expression self.name(*args, **kwargs).

Example

use pyo3::types::IntoPyDict;

let gil = Python::acquire_gil();
let py = gil.python();
let list = vec![3, 6, 5, 4, 7].to_object(py);
let dict = vec![("reverse", true)].into_py_dict(py);
list.call_method(py, "sort", (), Some(dict)).unwrap();
assert_eq!(list.extract::<Vec<i32>>(py).unwrap(), vec![7, 6, 5, 4, 3]);

let new_element = 1.to_object(py);
list.call_method(py, "append", (new_element,), None).unwrap();
assert_eq!(list.extract::<Vec<i32>>(py).unwrap(), vec![7, 6, 5, 4, 3, 1]);

Calls a method on the object without arguments.

This is equivalent to the Python expression self.name().

Calls a method on the object with only positional arguments.

This is equivalent to the Python expression self.name(*args).

Returns whether the object is considered to be true.

This is equivalent to the Python expression bool(self).

Returns whether the object is considered to be None.

This is equivalent to the Python expression self is None.

Returns true if the sequence or mapping has a length of 0.

This is equivalent to the Python expression len(self) == 0.

Gets an item from the collection.

This is equivalent to the Python expression self[key].

Sets a collection item value.

This is equivalent to the Python expression self[key] = value.

Deletes an item from the collection.

This is equivalent to the Python expression del self[key].

Takes an object and returns an iterator for it.

This is typically a new iterator but if the argument is an iterator, this returns itself.

Returns the Python type object for this object’s type.

Returns the Python type pointer for this object.

Casts the PyObject to a concrete Python object type.

This can cast only to native Python types, not types implemented in Rust.

Extracts some type from the Python object.

This is a wrapper function around FromPyObject::extract().

Returns the reference count for the Python object.

Computes the “repr” representation of self.

This is equivalent to the Python expression repr(self).

Computes the “str” representation of self.

This is equivalent to the Python expression str(self).

Retrieves the hash code of self.

This is equivalent to the Python expression hash(self).

Returns the length of the sequence or mapping.

This is equivalent to the Python expression len(self).

Returns the list of attributes of this object.

This is equivalent to the Python expression dir(self).

Checks whether this object is an instance of type T.

This is equivalent to the Python expression isinstance(self, T).

Trait Implementations

Gets the underlying FFI pointer, returns a borrowed pointer.

Performs the conversion.

Performs the conversion.

Formats the value using the given formatter. Read more

The resulting type after dereferencing.

Dereferences the value.

Formats the value using the given formatter. Read more

Performs the conversion.

Performs the conversion.

Extracts Self from the source PyObject.

Performs the conversion.

Performs the conversion.

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

Cast &PyAny to &Self without no type checking. Read more

Type of objects to store in PyObject struct

Base class

Layout

Layout of Basetype.

Initializer for layout

Utility type to make Py::as_ref work

Class name

Module name, if any

PyTypeObject instance for this type.

Checks if object is an instance of this type or a subclass of this type.

Class doc string

Type flags (ie PY_TYPE_FLAG_GC, PY_TYPE_FLAG_WEAKREF)

Checks if object is an instance of this type.

Converts self into a Python object.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

Convert from an arbitrary PyObject. Read more

Convert from an arbitrary borrowed PyObject. Read more

Convert from an arbitrary PyObject or panic. Read more

Convert from an arbitrary PyObject or panic. Read more

Convert from an arbitrary PyObject. Read more

Convert from an arbitrary borrowed PyObject. Read more

Convert from an arbitrary borrowed PyObject. Read more

Convert from an arbitrary borrowed PyObject. Read more

Performs the conversion.

Cast from a concrete Python object type to PyObject.

Cast from a concrete Python object type to PyObject. With exact type check.

Cast a PyAny to a specific type of PyObject. The caller must have already verified the reference is for this type. Read more

Returns the safe abstraction over the type object.

Converts self into a Python object and calls the specified closure on the native FFI pointer underlying the Python object. Read more

Converts the given value to a String. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.