Add implementation of dpnp.lib.stride_tricks.as_strided

CHANGELOG.md

@@ -15,6 +15,7 @@ This release is compatible with NumPy 2.5.
 * Added support for buffer protocol objects as advanced index keys in `dpnp.ndarray` [#2889](https://github.com/IntelPython/dpnp/pull/2889)
 * Added `--includes` and `--include-dir` options to the `dpnp` CLI [#2916](https://github.com/IntelPython/dpnp/pull/2916)
 * Added `dpnp-config.cmake` to make `find_package(Dpnp)` work out of the box, and an example which uses it [#2941](https://github.com/IntelPython/dpnp/pull/2941)
+* Added implementation of `dpnp.lib.stride_tricks.as_strided` [#2991](https://github.com/IntelPython/dpnp/pull/2991)
 
 ### Changed
 

doc/reference/lib.rst

@@ -0,0 +1,15 @@
+.. _routines.lib:
+.. module:: dpnp.lib
+
+Lib module (:mod:`dpnp.lib`)
+============================
+
+.. hint:: `NumPy API Reference: Lib module (numpy.lib) <https://numpy.org/doc/stable/reference/routines.lib.html>`_
+
+Submodules
+----------
+
+.. autosummary::
+   :toctree: generated/
+
+   stride_tricks

doc/reference/routines.rst

@@ -20,6 +20,7 @@ These functions cover a subset of
    functional
    io
    indexing
+   lib
    linalg
    logic
    math

dpnp/__init__.py

@@ -67,6 +67,7 @@
 from ._version import get_versions
 from . import exceptions as exceptions
 from . import fft as fft
+from . import lib as lib
 from . import linalg as linalg
 from . import random as random
 from . import scipy as scipy

dpnp/lib/__init__.py

@@ -0,0 +1,40 @@
+# *****************************************************************************
+# Copyright (c) 2026, Intel Corporation
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# - Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+# - Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+# - Neither the name of the copyright holder nor the names of its contributors
+#   may be used to endorse or promote products derived from this software
+#   without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+# THE POSSIBILITY OF SUCH DAMAGE.
+# *****************************************************************************
+
+"""
+``dpnp.lib``
+============
+
+The library of stride-manipulation utilities of DPNP.
+
+This namespace mimics parts of ``numpy.lib`` on top of DPNP functionality.
+"""
+
+from . import stride_tricks
+
+__all__ = ["stride_tricks"]

dpnp/lib/stride_tricks.py

@@ -0,0 +1,172 @@
+# *****************************************************************************
+# Copyright (c) 2026, Intel Corporation
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# - Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+# - Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+# - Neither the name of the copyright holder nor the names of its contributors
+#   may be used to endorse or promote products derived from this software
+#   without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+# THE POSSIBILITY OF SUCH DAMAGE.
+# *****************************************************************************
+
+"""Utilities that manipulate strides to achieve desirable effects."""
+
+import dpnp
+
+__all__ = ["as_strided"]
+
+
+def as_strided(
+    x,
+    shape=None,
+    strides=None,
+    subok=False,
+    writeable=True,
+    *,
+    check_bounds=None,
+):
+    """
+    Create a view into the array with the given shape and strides.
+
+    For full documentation refer to :obj:`numpy.lib.stride_tricks.as_strided`.
+
+    Warnings
+    --------
+    This function has to be used with extreme care, see notes.
+
+    Parameters
+    ----------
+    x : {dpnp.ndarray, usm_ndarray}
+        Array to create a new view from.
+    shape : {None, sequence of ints}, optional
+        The shape of the new array.
+
+        Default: ``x.shape``.
+    strides : {None, sequence of ints}, optional
+        The strides of the new array, expressed in bytes.
+
+        Default: ``x.strides``.
+    writeable : bool, optional
+        If set to ``False``, the returned array will always be read-only.
+        Otherwise it will be writable if the original array was.
+
+        Default: ``True``.
+    check_bounds : {None, bool}, optional
+        Ignored as no effect, the underlying USM array cannot be constructed
+        over out-of-bounds memory.
+
+        Default: ``None``.
+
+    Returns
+    -------
+    view : dpnp.ndarray
+        A view into the memory of `x` with the requested `shape` and `strides`,
+        sharing the same data.
+
+    Limitations
+    -----------
+    Parameter `subok` is supported with default value.
+    Otherwise ``NotImplementedError`` exception will be raised.
+
+    See Also
+    --------
+    :obj:`dpnp.broadcast_to` : Broadcast an array to a given shape.
+    :obj:`dpnp.reshape` : Give a new shape to an array without changing its
+        data.
+
+    Notes
+    -----
+    :obj:`dpnp.lib.stride_tricks.as_strided` creates a view into the array
+    given the exact strides and shape. This means it manipulates the internal
+    data structure of the array and, if done incorrectly, the array elements
+    can point to the wrong data and silently produce incorrect results. It is
+    advisable to always use the original ``x.strides`` when calculating new
+    strides to avoid reliance on a contiguous memory layout.
+
+    Furthermore, arrays created with this function often contain self
+    overlapping memory, so that two elements are identical. Writing to a shared
+    element then changes every position that references it, so element-wise
+    write operations on such arrays are typically unpredictable. A bulk write
+    over an overlapping view is rejected, because it would address more memory
+    than the base allocation holds.
+
+    Since writing to these arrays has to be tested and done with great care,
+    you may want to use ``writeable=False`` to avoid accidental write
+    operations.
+
+    For these reasons it is advisable to avoid
+    :obj:`dpnp.lib.stride_tricks.as_strided` when possible.
+
+    Examples
+    --------
+    >>> import dpnp as np
+    >>> x = np.array([1, 2, 3, 4], dtype=np.int32)
+
+    Downsample the array by taking every second element:
+
+    >>> np.lib.stride_tricks.as_strided(x, shape=(2,),
+    ...                                 strides=(2 * x.itemsize,))
+    array([1, 3], dtype=int32)
+
+    Broadcast the array along a new leading axis using a zero stride:
+
+    >>> np.lib.stride_tricks.as_strided(x, shape=(3, 4),
+    ...                                 strides=(0, x.itemsize))
+    array([[1, 2, 3, 4],
+           [1, 2, 3, 4],
+           [1, 2, 3, 4]], dtype=int32)
+
+    Build a self-overlapping sliding-window view, where a single element maps
+    onto several positions. Here a length-5 array yields a ``3x3`` window in
+    which each value repeats along the anti-diagonals:
+
+    >>> y = np.arange(5, dtype=np.int32)
+    >>> np.lib.stride_tricks.as_strided(y, shape=(3, 3),
+    ...                                 strides=(y.itemsize, y.itemsize))
+    array([[0, 1, 2],
+           [1, 2, 3],
+           [2, 3, 4]], dtype=int32)
+
+    Attempting to create an out-of-bounds view:
+
+    >>> np.lib.stride_tricks.as_strided(y, shape=(10,),
+    ...                                 strides=(y.itemsize,))
+    Traceback (most recent call last):
+    ...
+    ValueError: buffer='[0 1 2 3 4]' can not accommodate the requested array.
+
+    """
+
+    dpnp.check_supported_arrays_type(x)
+    dpnp.check_limitations(subok=subok)
+
+    shape = x.shape if shape is None else tuple(shape)
+    strides = x.strides if strides is None else tuple(strides)
+
+    view = dpnp.ndarray(
+        shape,
+        dtype=x.dtype,
+        buffer=x,
+        strides=strides,
+    )
+
+    if view.flags.writable and not writeable:
+        view.flags.writable = False
+    return view