Struct numpy::array::PyArray

#[repr(transparent)]
pub struct PyArray<T, D>(_, _, _);

A safe, statically-typed wrapper for NumPy’s ndarray class.

Memory location

• Allocated by Rust: Constructed via IntoPyArray or from_vec or from_owned_array.

These methods transfers ownership of the Rust allocation into a suitable Python object and uses the memory as the internal buffer backing the NumPy array.

Please note that some destructive methods like resize will fail when used with this kind of array as NumPy cannot reallocate the internal buffer.

• Allocated by NumPy: Constructed via other methods, like ToPyArray or from_slice or from_array.

These methods allocate memory in Python’s private heap via NumPy’s API.

In both cases, PyArray is managed by Python so it can neither be moved from nor deallocated manually.

References

Like new, all constructor methods of PyArray return a shared reference &PyArray instead of an owned value. This design follows PyO3’s ownership concept, i.e. the return value is GIL-bound owning reference into Python’s heap.

Element type and dimensionality

PyArray has two type parametes T and D. T represents the type of its elements, e.g. f32 or PyObject. D represents its dimensionality, e.g Ix2 or IxDyn.

Element types are Rust types which implement the Element trait. Dimensions are represented by the ndarray::Dimension trait.

Typically, Ix1, Ix2, ... are used for fixed dimensionality arrays, and IxDyn is used for dynamic dimensionality arrays. Type aliases for combining PyArray with these types are provided, e.g. PyArray1 or PyArrayDyn.

To specify concrete dimension like 3×4×5, types which implement the ndarray::IntoDimension trait are used. Typically, this means arrays like [3, 4, 5] or tuples like (3, 4, 5).

Example

use numpy::PyArray;
use ndarray::{array, Array};
use pyo3::Python;

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

impl<T, D> PyArray<T, D>

pub fn as_array_ptr(&self) -> *mut PyArrayObject

Returns a raw pointer to the underlying PyArrayObject.

pub fn dtype(&self) -> &PyArrayDescr

Returns the dtype of the array.

See also ndarray.dtype and PyArray_DTYPE.

Example

use numpy::{dtype, PyArray};
use pyo3::Python;

Python::with_gil(|py| {
   let array = PyArray::from_vec(py, vec![1_i32, 2, 3]);

   assert!(array.dtype().is_equiv_to(dtype::<i32>(py)));
});

pub fn is_contiguous(&self) -> bool

Returns true if the internal data of the array is contiguous, indepedently of whether C-style/row-major or Fortran-style/column-major.

Example

use numpy::PyArray1;
use pyo3::{types::IntoPyDict, Python};

Python::with_gil(|py| {
    let array = PyArray1::arange(py, 0, 10, 1);
    assert!(array.is_contiguous());

    let view = py
        .eval("array[::2]", None, Some([("array", array)].into_py_dict(py)))
        .unwrap()
        .downcast::<PyArray1<i32>>()
        .unwrap();
    assert!(!view.is_contiguous());
});

pub fn is_fortran_contiguous(&self) -> bool

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

pub fn is_c_contiguous(&self) -> bool

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

pub fn to_owned(&self) -> Py<Self>

Turn &PyArray<T,D> into Py<PyArray<T,D>>, i.e. a pointer into Python’s heap which is independent of the GIL lifetime.

This method can be used to avoid lifetime annotations of function arguments or return values.

Example

use numpy::PyArray1;
use pyo3::{Py, Python};

let array: Py<PyArray1<f64>> = Python::with_gil(|py| {
    PyArray1::zeros(py, 5, false).to_owned()
});

Python::with_gil(|py| {
    assert_eq!(array.as_ref(py).readonly().as_slice().unwrap(), [0.0; 5]);
});

pub unsafe fn from_owned_ptr<'py>(
    py: Python<'py>,
    ptr: *mut PyObject
) -> &'py Self

Constructs a reference to a PyArray from a raw pointer to a Python object.

Safety

This is a wrapper around pyo3::FromPyPointer::from_owned_ptr_or_opt and inherits its safety contract.

pub unsafe fn from_borrowed_ptr<'py>(
    py: Python<'py>,
    ptr: *mut PyObject
) -> &'py Self

Constructs a reference to a PyArray from a raw point to a Python object.

Safety

This is a wrapper around pyo3::FromPyPointer::from_borrowed_ptr_or_opt and inherits its safety contract.

pub fn ndim(&self) -> usize

Returns the number of dimensions of the array.

See also ndarray.ndim and PyArray_NDIM.

Example

use numpy::PyArray3;
use pyo3::Python;

Python::with_gil(|py| {
    let arr = PyArray3::<f64>::zeros(py, [4, 5, 6], false);

    assert_eq!(arr.ndim(), 3);
});

pub fn strides(&self) -> &[isize]

Returns a slice indicating how many bytes to advance when iterating along each axis.

See also ndarray.strides and PyArray_STRIDES.

Example

use numpy::PyArray3;
use pyo3::Python;

Python::with_gil(|py| {
    let arr = PyArray3::<f64>::zeros(py, [4, 5, 6], false);

    assert_eq!(arr.strides(), &[240, 48, 8]);
});

pub fn shape(&self) -> &[usize]

Returns a slice which contains dimmensions of the array.

See also [ndarray.shape][ndaray-shape] and PyArray_DIMS.

Example

use numpy::PyArray3;
use pyo3::Python;

Python::with_gil(|py| {
    let arr = PyArray3::<f64>::zeros(py, [4, 5, 6], false);

    assert_eq!(arr.shape(), &[4, 5, 6]);
});

pub fn len(&self) -> usize

Calculates the total number of elements in the array.

pub fn is_empty(&self) -> bool

Returns true if the there are no elements in the array.

pub fn data(&self) -> *mut T

Returns a pointer to the first element of the array.

impl<T: Element, D: Dimension> PyArray<T, D>

pub fn dims(&self) -> D

Same as shape, but returns D insead of &[usize].

pub unsafe fn new<ID>(py: Python<'_>, dims: ID, is_fortran: bool) -> &Selfwhere
    ID: IntoDimension<Dim = D>,

Creates a new uninitialized NumPy array.

If is_fortran is true, then it has Fortran/column-major order, otherwise it has C/row-major order.

Safety

The returned array will always be safe to be dropped as the elements must either be trivially copyable (as indicated by <T as Element>::IS_COPY) or be pointers into Python’s heap, which NumPy will automatically zero-initialize.

However, the elements themselves will not be valid and should be initialized manually using raw pointers obtained via uget_raw. Before that, all methods which produce references to the elements invoke undefined behaviour. In particular, zero-initialized pointers are not valid instances of PyObject.

Example

use numpy::PyArray3;
use pyo3::Python;

Python::with_gil(|py| {
    let arr = unsafe {
        let arr = PyArray3::<i32>::new(py, [4, 5, 6], false);

        for i in 0..4 {
            for j in 0..5 {
                for k in 0..6 {
                    arr.uget_raw([i, j, k]).write((i * j * k) as i32);
                }
            }
        }

        arr
    };

    assert_eq!(arr.shape(), &[4, 5, 6]);
});

pub unsafe fn borrow_from_array<'py, S>(
    array: &ArrayBase<S, D>,
    container: &'py PyAny
) -> &'py Selfwhere
    S: Data<Elem = T>,

Creates a NumPy array backed by array and ties its ownership to the Python object container.

Safety

container is set as a base object of the returned array which must not be dropped until container is dropped. Furthermore, array must not be reallocated from the time this method is called and until container is dropped.

Example

#[pyclass]
struct Owner {
    array: Array1<f64>,
}

#[pymethods]
impl Owner {
    #[getter]
    fn array<'py>(this: &'py PyCell<Self>) -> &'py PyArray1<f64> {
        let array = &this.borrow().array;

        // SAFETY: The memory backing `array` will stay valid as long as this object is alive
        // as we do not modify `array` in any way which would cause it to be reallocated.
        unsafe { PyArray1::borrow_from_array(array, this) }
    }
}

pub fn zeros<ID>(py: Python<'_>, dims: ID, is_fortran: bool) -> &Selfwhere
    ID: IntoDimension<Dim = D>,

Construct a new NumPy array filled with zeros.

If is_fortran is true, then it has Fortran/column-major order, otherwise it has C/row-major order.

For arrays of Python objects, this will fill the array with valid pointers to zero-valued Python integer objects.

See also numpy.zeros and PyArray_Zeros.

Example

use numpy::PyArray2;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray: &PyArray2<usize> = PyArray2::zeros(py, [2, 2], true);

    assert_eq!(pyarray.readonly().as_slice().unwrap(), [0; 4]);
});

pub unsafe fn as_slice(&self) -> Result<&[T], NotContiguousError>

Returns an immutable view of the internal data as a slice.

Safety

Calling this method is undefined behaviour if the underlying array is aliased mutably by other instances of PyArray or concurrently modified by Python or other native code.

Please consider the safe alternative PyReadonlyArray::as_slice.

pub unsafe fn as_slice_mut(&self) -> Result<&mut [T], NotContiguousError>

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

Safety

Calling this method is undefined behaviour if the underlying array is aliased immutably or mutably by other instances of PyArray or concurrently modified by Python or other native code.

Please consider the safe alternative PyReadwriteArray::as_slice_mut.

pub fn from_owned_array<'py>(py: Python<'py>, arr: Array<T, D>) -> &'py Self

Constructs a NumPy from an ndarray::Array

This method uses the internal Vec of the ndarray::Array as the base object of the NumPy array.

Example

use numpy::PyArray;
use ndarray::array;
use pyo3::Python;

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]]);
});

pub unsafe fn get(&self, index: impl NpyIndex<Dim = D>) -> Option<&T>

Get a reference of the specified element if the given index is valid.

Safety

Calling this method is undefined behaviour if the underlying array is aliased mutably by other instances of PyArray or concurrently modified by Python or other native code.

Consider using safe alternatives like PyReadonlyArray::get.

Example

use numpy::PyArray;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray = PyArray::arange(py, 0, 16, 1).reshape([2, 2, 4]).unwrap();

    assert_eq!(unsafe { *pyarray.get([1, 0, 3]).unwrap() }, 11);
});

pub unsafe fn get_mut(&self, index: impl NpyIndex<Dim = D>) -> Option<&mut T>

Same as get, but returns Option<&mut T>.

Safety

Calling this method is undefined behaviour if the underlying array is aliased immutably or mutably by other instances of PyArray or concurrently modified by Python or other native code.

Consider using safe alternatives like PyReadwriteArray::get_mut.

Example

use numpy::PyArray;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray = PyArray::arange(py, 0, 16, 1).reshape([2, 2, 4]).unwrap();

    unsafe {
        *pyarray.get_mut([1, 0, 3]).unwrap() = 42;
    }

    assert_eq!(unsafe { *pyarray.get([1, 0, 3]).unwrap() }, 42);
});

pub unsafe fn uget<Idx>(&self, index: Idx) -> &Twhere
    Idx: NpyIndex<Dim = D>,

Get an immutable reference of the specified element, without checking the given index.

See NpyIndex for what types can be used as the index.

Safety

Passing an invalid index is undefined behavior. The element must also have been initialized and all other references to it is must also be shared.

See PyReadonlyArray::get for a safe alternative.

Example

use numpy::PyArray;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray = PyArray::arange(py, 0, 16, 1).reshape([2, 2, 4]).unwrap();

    assert_eq!(unsafe { *pyarray.uget([1, 0, 3]) }, 11);
});

pub unsafe fn uget_mut<Idx>(&self, index: Idx) -> &mut Twhere
    Idx: NpyIndex<Dim = D>,

Same as uget, but returns &mut T.

Safety

Passing an invalid index is undefined behavior. The element must also have been initialized and other references to it must not exist.

See PyReadwriteArray::get_mut for a safe alternative.

pub unsafe fn uget_raw<Idx>(&self, index: Idx) -> *mut Twhere
    Idx: NpyIndex<Dim = D>,

Same as uget, but returns *mut T.

Safety

Passing an invalid index is undefined behavior.

pub fn get_owned<Idx>(&self, index: Idx) -> Option<T>where
    Idx: NpyIndex<Dim = D>,

Get a copy of the specified element in the array.

See NpyIndex for what types can be used as the index.

Example

use numpy::PyArray;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray = PyArray::arange(py, 0, 16, 1).reshape([2, 2, 4]).unwrap();

    assert_eq!(pyarray.get_owned([1, 0, 3]), Some(11));
});

pub fn to_dyn(&self) -> &PyArray<T, IxDyn>

Turn an array with fixed dimensionality into one with dynamic dimensionality.

pub fn to_vec(&self) -> Result<Vec<T>, NotContiguousError>

Returns a copy of the internal data of the array as a Vec.

Fails if the internal array is not contiguous. See also as_slice.

Example

use numpy::PyArray2;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray= py
        .eval("__import__('numpy').array([[0, 1], [2, 3]], dtype='int64')", None, None)
        .unwrap()
        .downcast::<PyArray2<i64>>()
        .unwrap();

    assert_eq!(pyarray.to_vec().unwrap(), vec![0, 1, 2, 3]);
});

pub fn from_array<'py, S>(py: Python<'py>, arr: &ArrayBase<S, D>) -> &'py Selfwhere
    S: Data<Elem = T>,

Construct a NumPy array from a ndarray::ArrayBase.

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

Example

use numpy::PyArray;
use ndarray::array;
use pyo3::Python;

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]]);
});

pub fn try_readonly(&self) -> Result<PyReadonlyArray<'_, T, D>, BorrowError>

Get an immutable borrow of the NumPy array

pub fn readonly(&self) -> PyReadonlyArray<'_, T, D>

Get an immutable borrow of the NumPy array

Panics

Panics if the allocation backing the array is currently mutably borrowed.

For a non-panicking variant, use try_readonly.

pub fn try_readwrite(&self) -> Result<PyReadwriteArray<'_, T, D>, BorrowError>

Get a mutable borrow of the NumPy array

pub fn readwrite(&self) -> PyReadwriteArray<'_, T, D>

Get a mutable borrow of the NumPy array

Panics

Panics if the allocation backing the array is currently borrowed or if the array is flagged as not writeable.

For a non-panicking variant, use try_readwrite.

pub unsafe fn as_array(&self) -> ArrayView<'_, T, D>

Returns an ArrayView of the internal array.

See also PyReadonlyArray::as_array.

Safety

The existence of an exclusive reference to the internal data, e.g. &mut [T] or ArrayViewMut, implies undefined behavior.

pub unsafe fn as_array_mut(&self) -> ArrayViewMut<'_, T, D>

Returns an ArrayViewMut of the internal array.

See also PyReadwriteArray::as_array_mut.

Safety

The existence of another reference to the internal data, e.g. &[T] or ArrayView, implies undefined behavior.

pub fn as_raw_array(&self) -> RawArrayView<T, D>

Returns the internal array as RawArrayView enabling element access via raw pointers

pub fn as_raw_array_mut(&self) -> RawArrayViewMut<T, D>

Returns the internal array as RawArrayViewMut enabling element access via raw pointers

pub fn to_owned_array(&self) -> Array<T, D>

Get a copy of the array as an ndarray::Array.

Example

use numpy::PyArray;
use ndarray::array;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray = PyArray::arange(py, 0, 4, 1).reshape([2, 2]).unwrap();

    assert_eq!(
        pyarray.to_owned_array(),
        array![[0, 1], [2, 3]]
    )
});

impl<D: Dimension> PyArray<PyObject, D>

pub fn from_owned_object_array<'py, T>(
    py: Python<'py>,
    arr: Array<Py<T>, D>
) -> &'py Self

Construct a NumPy array containing objects stored in a ndarray::Array

This method uses the internal Vec of the ndarray::Array as the base object of the NumPy array.

Example

use ndarray::array;
use pyo3::{pyclass, Py, Python};
use numpy::PyArray;

#[pyclass]
struct CustomElement {
    foo: i32,
    bar: f64,
}

Python::with_gil(|py| {
    let array = array![
        Py::new(py, CustomElement {
            foo: 1,
            bar: 2.0,
        }).unwrap(),
        Py::new(py, CustomElement {
            foo: 3,
            bar: 4.0,
        }).unwrap(),
    ];

    let pyarray = PyArray::from_owned_object_array(py, array);

    assert!(pyarray.readonly().as_array().get(0).unwrap().as_ref(py).is_instance_of::<CustomElement>().unwrap());
});

impl<T: Copy + Element> PyArray<T, Ix0>

pub fn item(&self) -> T

Get the single element of a zero-dimensional array.

See inner for an example.

impl<T: Element> PyArray<T, Ix1>

pub fn from_slice<'py>(py: Python<'py>, slice: &[T]) -> &'py Self

Construct a one-dimensional array from a slice.

Example

use numpy::PyArray;
use pyo3::Python;

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

pub fn from_vec<'py>(py: Python<'py>, vec: Vec<T>) -> &'py Self

Construct a one-dimensional array from a Vec<T>.

Example

use numpy::PyArray;
use pyo3::Python;

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

pub fn from_exact_iter<I>(py: Python<'_>, iter: I) -> &Selfwhere
    I: IntoIterator<Item = T>,
    I::IntoIter: ExactSizeIterator,

👎Deprecated since 0.17.0:

from_exact_iter is deprecated as it does not provide any benefit over from_iter.

Construct a one-dimensional array from an ExactSizeIterator.

Example

use numpy::PyArray;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray = PyArray::from_exact_iter(py, [1, 2, 3, 4, 5].into_iter().copied());
    assert_eq!(pyarray.readonly().as_slice().unwrap(), &[1, 2, 3, 4, 5]);
});

pub fn from_iter<I>(py: Python<'_>, iter: I) -> &Selfwhere
    I: IntoIterator<Item = T>,

Construct a one-dimensional array from an Iterator.

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

Example

use numpy::PyArray;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray = PyArray::from_iter(py, "abcde".chars().map(u32::from));
    assert_eq!(pyarray.readonly().as_slice().unwrap(), &[97, 98, 99, 100, 101]);
});

impl<T: Element> PyArray<T, Ix2>

pub fn from_vec2<'py>(
    py: Python<'py>,
    v: &[Vec<T>]
) -> Result<&'py Self, FromVecError>

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

This function checks all dimensions of the inner vectors and returns an error if they are not all equal.

Example

use numpy::PyArray;
use pyo3::Python;
use ndarray::array;

Python::with_gil(|py| {
    let vec2 = vec![vec![11, 12], vec![21, 22]];
    let pyarray = PyArray::from_vec2(py, &vec2).unwrap();
    assert_eq!(pyarray.readonly().as_array(), array![[11, 12], [21, 22]]);

    let ragged_vec2 = vec![vec![11, 12], vec![21]];
    assert!(PyArray::from_vec2(py, &ragged_vec2).is_err());
});

impl<T: Element> PyArray<T, Ix3>

pub fn from_vec3<'py>(
    py: Python<'py>,
    v: &[Vec<Vec<T>>]
) -> Result<&'py Self, FromVecError>

Construct a three-dimensional array from a Vec<Vec<Vec<T>>>.

This function checks all dimensions of the inner vectors and returns an error if they are not all equal.

Example

use numpy::PyArray;
use pyo3::Python;
use ndarray::array;

Python::with_gil(|py| {
    let vec3 = vec![
        vec![vec![111, 112], vec![121, 122]],
        vec![vec![211, 212], vec![221, 222]],
    ];
    let pyarray = PyArray::from_vec3(py, &vec3).unwrap();
    assert_eq!(
        pyarray.readonly().as_array(),
        array![[[111, 112], [121, 122]], [[211, 212], [221, 222]]]
    );

    let ragged_vec3 = vec![
        vec![vec![111, 112], vec![121, 122]],
        vec![vec![211], vec![221, 222]],
    ];
    assert!(PyArray::from_vec3(py, &ragged_vec3).is_err());
});

impl<T: Element, D> PyArray<T, D>

pub fn copy_to<U: Element>(&self, other: &PyArray<U, D>) -> PyResult<()>

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

See also PyArray_CopyInto.

Example

use numpy::PyArray;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray_f = PyArray::arange(py, 2.0, 5.0, 1.0);
    let pyarray_i = unsafe { 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]);
});

pub fn cast<'py, U: Element>(
    &'py self,
    is_fortran: bool
) -> PyResult<&'py PyArray<U, D>>

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

See also PyArray_CastToType.

Example

use numpy::PyArray;
use pyo3::Python;

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_eq!(pyarray_i.readonly().as_slice().unwrap(), &[2, 3, 4]);
});

pub fn reshape_with_order<'py, ID: IntoDimension>(
    &'py self,
    dims: ID,
    order: NPY_ORDER
) -> PyResult<&'py PyArray<T, ID::Dim>>

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

See also numpy.reshape and PyArray_Newshape.

Example

use numpy::{npyffi::NPY_ORDER, PyArray};
use pyo3::Python;
use ndarray::array;

Python::with_gil(|py| {
    let array =
        PyArray::from_iter(py, 0..9).reshape_with_order([3, 3], NPY_ORDER::NPY_FORTRANORDER).unwrap();

    assert_eq!(array.readonly().as_array(), array![[0, 3, 6], [1, 4, 7], [2, 5, 8]]);
    assert!(array.is_fortran_contiguous());

    assert!(array.reshape([5]).is_err());
});

pub fn reshape<'py, ID: IntoDimension>(
    &'py self,
    dims: ID
) -> PyResult<&'py PyArray<T, ID::Dim>>

Special case of reshape_with_order which keeps the memory order the same.

pub unsafe fn resize<ID: IntoDimension>(&self, dims: ID) -> PyResult<()>

Extends or truncates the dimensions of an array.

This method works only on contiguous arrays. Missing elements will be initialized as if calling zeros.

See also ndarray.resize and PyArray_Resize.

Safety

There should be no outstanding references (shared or exclusive) into the array as this method might re-allocate it and thereby invalidate all pointers into it.

Example

use numpy::PyArray;
use pyo3::Python;

Python::with_gil(|py| {
    let pyarray = PyArray::<f64, _>::zeros(py, (10, 10), false);
    assert_eq!(pyarray.shape(), [10, 10]);

    unsafe {
        pyarray.resize((100, 100)).unwrap();
    }
    assert_eq!(pyarray.shape(), [100, 100]);
});

impl<T: Element + AsPrimitive<f64>> PyArray<T, Ix1>

pub fn arange(py: Python<'_>, start: T, stop: T, step: T) -> &Self

Return evenly spaced values within a given interval.

See numpy.arange for the Python API and PyArray_Arange for the C API.

Example

use numpy::PyArray;
use pyo3::Python;

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>

pub fn downcast<T>(&self) -> Result<&T, PyDowncastError<'_>>where
    T: for<'py> PyTryFrom<'py>,

Converts this PyAny to a concrete Python type.

Examples

use pyo3::prelude::*;
use pyo3::types::{PyAny, PyDict, PyList};

Python::with_gil(|py| {
    let dict = PyDict::new(py);
    assert!(dict.is_instance_of::<PyAny>().unwrap());
    let any: &PyAny = dict.as_ref();
    assert!(any.downcast::<PyDict>().is_ok());
    assert!(any.downcast::<PyList>().is_err());
});

pub fn is<T>(&self, other: &T) -> boolwhere
    T: AsPyPointer,

Returns whether self and other point to the same object. To compare the equality of two objects (the == operator), use eq.

This is equivalent to the Python expression self is other.

pub fn hasattr<N>(&self, attr_name: N) -> Result<bool, PyErr>where
    N: IntoPy<Py<PyString>>,

Determines whether this object has the given attribute.

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

To avoid repeated temporary allocations of Python strings, the [intern!] macro can be used to intern attr_name.

pub fn getattr<N>(&self, attr_name: N) -> Result<&PyAny, PyErr>where
    N: IntoPy<Py<PyString>>,

Retrieves an attribute value.

This is equivalent to the Python expression self.attr_name.

To avoid repeated temporary allocations of Python strings, the [intern!] macro can be used to intern attr_name.

Example: intern!ing the attribute name

#[pyfunction]
fn version(sys: &PyModule) -> PyResult<&PyAny> {
    sys.getattr(intern!(sys.py(), "version"))
}

pub fn setattr<N, V>(&self, attr_name: N, value: V) -> Result<(), PyErr>where
    N: IntoPy<Py<PyString>>,
    V: ToPyObject,

Sets an attribute value.

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

To avoid repeated temporary allocations of Python strings, the [intern!] macro can be used to intern name.

Example: intern!ing the attribute name

#[pyfunction]
fn set_answer(ob: &PyAny) -> PyResult<()> {
    ob.setattr(intern!(ob.py(), "answer"), 42)
}

pub fn delattr<N>(&self, attr_name: N) -> Result<(), PyErr>where
    N: IntoPy<Py<PyString>>,

Deletes an attribute.

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

To avoid repeated temporary allocations of Python strings, the [intern!] macro can be used to intern attr_name.

pub fn compare<O>(&self, other: O) -> Result<Ordering, PyErr>where
    O: ToPyObject,

Returns an Ordering between self and other.

This is equivalent to the following Python code:

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

Examples

use pyo3::prelude::*;
use pyo3::types::PyFloat;
use std::cmp::Ordering;

Python::with_gil(|py| -> PyResult<()> {
    let a = PyFloat::new(py, 0_f64);
    let b = PyFloat::new(py, 42_f64);
    assert_eq!(a.compare(b)?, Ordering::Less);
    Ok(())
})?;

It will return PyErr for values that cannot be compared:

use pyo3::prelude::*;
use pyo3::types::{PyFloat, PyString};

Python::with_gil(|py| -> PyResult<()> {
    let a = PyFloat::new(py, 0_f64);
    let b = PyString::new(py, "zero");
    assert!(a.compare(b).is_err());
    Ok(())
})?;

pub fn rich_compare<O>(
    &self,
    other: O,
    compare_op: CompareOp
) -> Result<&PyAny, PyErr>where
    O: ToPyObject,

Tests whether two Python objects obey a given CompareOp.

lt, le, eq, ne, gt and ge are the specialized versions of this function.

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

compare_op	Python expression
CompareOp::Eq	self == other
CompareOp::Ne	self != other
CompareOp::Lt	self < other
CompareOp::Le	self <= other
CompareOp::Gt	self > other
CompareOp::Ge	self >= other

Examples

use pyo3::class::basic::CompareOp;
use pyo3::prelude::*;
use pyo3::types::PyInt;

Python::with_gil(|py| -> PyResult<()> {
    let a: &PyInt = 0_u8.into_py(py).into_ref(py).downcast()?;
    let b: &PyInt = 42_u8.into_py(py).into_ref(py).downcast()?;
    assert!(a.rich_compare(b, CompareOp::Le)?.is_true()?);
    Ok(())
})?;

pub fn lt<O>(&self, other: O) -> Result<bool, PyErr>where
    O: ToPyObject,

Tests whether this object is less than another.

This is equivalent to the Python expression self < other.

pub fn le<O>(&self, other: O) -> Result<bool, PyErr>where
    O: ToPyObject,

Tests whether this object is less than or equal to another.

This is equivalent to the Python expression self <= other.

pub fn eq<O>(&self, other: O) -> Result<bool, PyErr>where
    O: ToPyObject,

Tests whether this object is equal to another.

This is equivalent to the Python expression self == other.

pub fn ne<O>(&self, other: O) -> Result<bool, PyErr>where
    O: ToPyObject,

Tests whether this object is not equal to another.

This is equivalent to the Python expression self != other.

pub fn gt<O>(&self, other: O) -> Result<bool, PyErr>where
    O: ToPyObject,

Tests whether this object is greater than another.

This is equivalent to the Python expression self > other.

pub fn ge<O>(&self, other: O) -> Result<bool, PyErr>where
    O: ToPyObject,

Tests whether this object is greater than or equal to another.

This is equivalent to the Python expression self >= other.

pub fn is_callable(&self) -> bool

Determines whether this object appears callable.

This is equivalent to Python’s callable() function.

Examples

use pyo3::prelude::*;

Python::with_gil(|py| -> PyResult<()> {
    let builtins = PyModule::import(py, "builtins")?;
    let print = builtins.getattr("print")?;
    assert!(print.is_callable());
    Ok(())
})?;

This is equivalent to the Python statement assert callable(print).

Note that unless an API needs to distinguish between callable and non-callable objects, there is no point in checking for callability. Instead, it is better to just do the call and handle potential exceptions.

pub fn call(
    &self,
    args: impl IntoPy<Py<PyTuple>>,
    kwargs: Option<&PyDict>
) -> Result<&PyAny, PyErr>

Calls the object.

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

Examples

use pyo3::prelude::*;
use pyo3::types::PyDict;

const CODE: &str = r#"
def function(*args, **kwargs):
    assert args == ("hello",)
    assert kwargs == {"cruel": "world"}
    return "called with args and kwargs"
"#;

Python::with_gil(|py| {
    let module = PyModule::from_code(py, CODE, "", "")?;
    let fun = module.getattr("function")?;
    let args = ("hello",);
    let kwargs = PyDict::new(py);
    kwargs.set_item("cruel", "world")?;
    let result = fun.call(args, Some(kwargs))?;
    assert_eq!(result.extract::<&str>()?, "called with args and kwargs");
    Ok(())
})

pub fn call0(&self) -> Result<&PyAny, PyErr>

Calls the object without arguments.

This is equivalent to the Python expression self().

Examples

use pyo3::prelude::*;

Python::with_gil(|py| -> PyResult<()> {
    let module = PyModule::import(py, "builtins")?;
    let help = module.getattr("help")?;
    help.call0()?;
    Ok(())
})?;

This is equivalent to the Python expression help().

pub fn call1(&self, args: impl IntoPy<Py<PyTuple>>) -> Result<&PyAny, PyErr>

Calls the object with only positional arguments.

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

Examples

use pyo3::prelude::*;

const CODE: &str = r#"
def function(*args, **kwargs):
    assert args == ("hello",)
    assert kwargs == {}
    return "called with args"
"#;

Python::with_gil(|py| {
    let module = PyModule::from_code(py, CODE, "", "")?;
    let fun = module.getattr("function")?;
    let args = ("hello",);
    let result = fun.call1(args)?;
    assert_eq!(result.extract::<&str>()?, "called with args");
    Ok(())
})

pub fn call_method<N, A>(
    &self,
    name: N,
    args: A,
    kwargs: Option<&PyDict>
) -> Result<&PyAny, PyErr>where
    N: IntoPy<Py<PyString>>,
    A: IntoPy<Py<PyTuple>>,

Calls a method on the object.

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

To avoid repeated temporary allocations of Python strings, the [intern!] macro can be used to intern name.

Examples

use pyo3::prelude::*;
use pyo3::types::PyDict;

const CODE: &str = r#"
class A:
    def method(self, *args, **kwargs):
        assert args == ("hello",)
        assert kwargs == {"cruel": "world"}
        return "called with args and kwargs"
a = A()
"#;

Python::with_gil(|py| {
    let module = PyModule::from_code(py, CODE, "", "")?;
    let instance = module.getattr("a")?;
    let args = ("hello",);
    let kwargs = PyDict::new(py);
    kwargs.set_item("cruel", "world")?;
    let result = instance.call_method("method", args, Some(kwargs))?;
    assert_eq!(result.extract::<&str>()?, "called with args and kwargs");
    Ok(())
})

pub fn call_method0<N>(&self, name: N) -> Result<&PyAny, PyErr>where
    N: IntoPy<Py<PyString>>,

Calls a method on the object without arguments.

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

To avoid repeated temporary allocations of Python strings, the [intern!] macro can be used to intern name.

Examples

use pyo3::prelude::*;

const CODE: &str = r#"
class A:
    def method(self, *args, **kwargs):
        assert args == ()
        assert kwargs == {}
        return "called with no arguments"
a = A()
"#;

Python::with_gil(|py| {
    let module = PyModule::from_code(py, CODE, "", "")?;
    let instance = module.getattr("a")?;
    let result = instance.call_method0("method")?;
    assert_eq!(result.extract::<&str>()?, "called with no arguments");
    Ok(())
})

pub fn call_method1<N, A>(&self, name: N, args: A) -> Result<&PyAny, PyErr>where
    N: IntoPy<Py<PyString>>,
    A: IntoPy<Py<PyTuple>>,

Calls a method on the object with only positional arguments.

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

To avoid repeated temporary allocations of Python strings, the [intern!] macro can be used to intern name.

Examples

use pyo3::prelude::*;

const CODE: &str = r#"
class A:
    def method(self, *args, **kwargs):
        assert args == ("hello",)
        assert kwargs == {}
        return "called with args"
a = A()
"#;

Python::with_gil(|py| {
    let module = PyModule::from_code(py, CODE, "", "")?;
    let instance = module.getattr("a")?;
    let args = ("hello",);
    let result = instance.call_method1("method", args)?;
    assert_eq!(result.extract::<&str>()?, "called with args");
    Ok(())
})

pub fn is_true(&self) -> Result<bool, PyErr>

Returns whether the object is considered to be true.

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

pub fn is_none(&self) -> bool

Returns whether the object is considered to be None.

This is equivalent to the Python expression self is None.

pub fn is_empty(&self) -> Result<bool, PyErr>

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

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

pub fn get_item<K>(&self, key: K) -> Result<&PyAny, PyErr>where
    K: ToPyObject,

Gets an item from the collection.

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

pub fn set_item<K, V>(&self, key: K, value: V) -> Result<(), PyErr>where
    K: ToPyObject,
    V: ToPyObject,

Sets a collection item value.

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

pub fn del_item<K>(&self, key: K) -> Result<(), PyErr>where
    K: ToPyObject,

Deletes an item from the collection.

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

pub fn iter(&self) -> Result<&PyIterator, PyErr>

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.

pub fn get_type(&self) -> &PyType

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

pub fn get_type_ptr(&self) -> *mut PyTypeObject

Returns the Python type pointer for this object.

pub fn cast_as<'a, D>(&'a self) -> Result<&'a D, PyDowncastError<'a>>where
    D: PyTryFrom<'a>,

Casts self to a concrete Python object type.

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

pub fn extract<'a, D>(&'a self) -> Result<D, PyErr>where
    D: FromPyObject<'a>,

Extracts some type from the Python object.

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

pub fn get_refcnt(&self) -> isize

Returns the reference count for the Python object.

pub fn repr(&self) -> Result<&PyString, PyErr>

Computes the “repr” representation of self.

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

pub fn str(&self) -> Result<&PyString, PyErr>

Computes the “str” representation of self.

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

pub fn hash(&self) -> Result<isize, PyErr>

Retrieves the hash code of self.

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

pub fn len(&self) -> Result<usize, PyErr>

Returns the length of the sequence or mapping.

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

pub fn dir(&self) -> &PyList

Returns the list of attributes of this object.

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

pub fn is_instance(&self, ty: &PyType) -> Result<bool, PyErr>

Checks whether this object is an instance of type ty.

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

pub fn is_instance_of<T>(&self) -> Result<bool, PyErr>where
    T: PyTypeInfo,

Checks whether this object is an instance of type T.

This is equivalent to the Python expression isinstance(self, T), if the type T is known at compile time.

pub fn contains<V>(&self, value: V) -> Result<bool, PyErr>where
    V: ToPyObject,

Determines if self contains value.

This is equivalent to the Python expression value in self.

pub fn py(&self) -> Python<'_>

Returns a GIL marker constrained to the lifetime of this type.

pub fn py_super(&self) -> Result<&PySuper, PyErr>

Return a proxy object that delegates method calls to a parent or sibling class of type.

This is equivalent to the Python expression super()

Trait Implementations

impl<T, D> AsPyPointer for PyArray<T, D>

fn as_ptr(&self) -> *mut PyObject

Gets the underlying FFI pointer, returns a borrowed pointer.

impl<T, D> AsRef<PyAny> for PyArray<T, D>

fn as_ref(&self) -> &PyAny

Converts this type into a shared reference of the (usually inferred) input type.

impl<T, D> Debug for PyArray<T, D>

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<T, D> Deref for PyArray<T, D>

type Target = PyAny

The resulting type after dereferencing.

fn deref(&self) -> &PyAny

Dereferences the value.

impl<T, D> Display for PyArray<T, D>

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'a, T, D> From<&'a PyArray<T, D>> for &'a PyAny

fn from(ob: &'a PyArray<T, D>) -> Self

Converts to this type from the input type.

impl<T, D> From<&PyArray<T, D>> for Py<PyArray<T, D>>

fn from(other: &PyArray<T, D>) -> Self

Converts to this type from the input type.

impl<'py, T: Element, D: Dimension> FromPyObject<'py> for &'py PyArray<T, D>

fn extract(ob: &'py PyAny) -> PyResult<Self>

Extracts Self from the source PyObject.

impl<T, D> IntoPy<Py<PyAny>> for PyArray<T, D>

fn into_py(self, py: Python<'_>) -> PyObject

Performs the conversion.

impl<T, D> IntoPy<Py<PyArray<T, D>>> for &PyArray<T, D>

fn into_py(self, py: Python<'_>) -> Py<PyArray<T, D>>

Performs the conversion.

impl<T, D> PyNativeType for PyArray<T, D>

fn py(&self) -> Python<'_>

Returns a GIL marker constrained to the lifetime of this type.

unsafe fn unchecked_downcast(obj: &PyAny) -> &Self

Cast &PyAny to &Self without no type checking.

impl<T: Element, D: Dimension> PyTypeInfo for PyArray<T, D>

type AsRefTarget = PyArray<T, D>

Utility type to make Py::as_ref work.

const NAME: &'static str = "PyArray<T, D>"

Class name.

const MODULE: Option<&'static str> = _

Module name, if any.

fn type_object_raw(py: Python<'_>) -> *mut PyTypeObject

Returns the PyTypeObject instance for this type.

fn is_type_of(ob: &PyAny) -> bool

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

fn type_object(py: Python<'_>) -> &PyType

Returns the safe abstraction over the type object.

fn is_exact_type_of(object: &PyAny) -> bool

Checks if object is an instance of this type.

impl<T, D> ToPyObject for PyArray<T, D>

fn to_object(&self, py: Python<'_>) -> PyObject

Converts self into a Python object.