Add dpnp.byte_bounds implementation

dpnp/__init__.py

@@ -54,9 +54,13 @@
 from dpnp.dpnp_iface_types import *
 from dpnp.dpnp_iface import *
 from dpnp.dpnp_iface import __all__ as _iface__all__
+from dpnp.dpnp_iface_utils import *
+from dpnp.dpnp_iface_utils import __all__ as _ifaceutils__all__
 from dpnp._version import get_versions
 
 __all__ = _iface__all__
+__all__ += _ifaceutils__all__
+
 
 __version__ = get_versions()["version"]
 del get_versions

dpnp/dpnp_iface_utils.py

@@ -0,0 +1,70 @@
+# -*- coding: utf-8 -*-
+# *****************************************************************************
+# Copyright (c) 2016-2024, 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.
+#
+# 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.
+# *****************************************************************************
+
+"""
+Interface of the utils function of the DPNP
+
+Notes
+-----
+This module is a face or public interface file for the library
+
+"""
+
+import dpnp
+
+__all__ = ["byte_bounds"]
+
+
+def byte_bounds(a):
+    """
+    Returns a 2-tuple with pointers to the end-points of the array.
+
+    For full documentation refer to
+      :obj:`dpctl.tensor.usm_ndarray._byte_bounds`.
+
+    Parameters
+    ----------
+    a : usm_ndarray
+        Input array
+
+    Returns
+    -------
+    (beg, end) : tuple of 2 integers
+    The first integer is the first byte of the array, the second
+        integer is just past the last byte of the array
+
+    Examples
+    --------
+    >>> import dpnp as np
+    >>> x = np.ones((3, 10, 7))
+    >>> y = np.flip(x[:, 1::2], axis=1)
+    >>> beg_p, end_p = np.byte_bounds(y)
+    Bytes taken to store this array
+    >>> bytes_extent = end_p - beg_p
+
+    """
+
+    return dpnp.get_usm_ndarray(a)._byte_bounds

tests/test_usm_utils.py

@@ -0,0 +1,42 @@
+import dpctl.tensor as dpt
+from numpy.testing import assert_equal
+
+import dpnp
+
+
+def test_byte_bounds():
+    a = dpt.usm_ndarray((3, 4), dtype="int64", buffer="shared")
+    values = dpt.arange(12, dtype="int64")
+    for i in range(3):
+        a[i, :] = values[i * 4 : (i + 1) * 4]
+    low, high = dpnp.byte_bounds(a)
+    assert_equal(high - low, a.size * a.itemsize)
+
+
+def test_unusual_order_positive_stride():
+    a = dpt.usm_ndarray((3, 4), dtype="int64", buffer="shared")
+    values = dpt.arange(12, dtype="int64")
+    for i in range(3):
+        a[i, :] = values[i * 4 : (i + 1) * 4]
+    b = a.T
+    low, high = dpnp.byte_bounds(b)
+    assert_equal(high - low, b.size * b.itemsize)
+
+
+def test_unusual_order_negative_stride():
+    a = dpt.usm_ndarray((3, 4), dtype="int64", buffer="shared")
+    values = dpt.arange(12, dtype="int64")
+    for i in range(3):
+        a[i, :] = values[i * 4 : (i + 1) * 4]
+    b = a.T[::-1]
+    low, high = dpnp.byte_bounds(b)
+    assert_equal(high - low, b.size * b.itemsize)
+
+
+def test_strided():
+    a = dpt.usm_ndarray(12, dtype="int64", buffer="shared")
+    a[:] = dpt.arange(12, dtype="int64")
+    b = a[::2]
+    low, high = dpnp.byte_bounds(b)
+    expected_byte_diff = b.size * 2 * b.itemsize - b.itemsize
+    assert_equal(high - low, expected_byte_diff)