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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Bug in `asnumpy` copy_utils","articleBody":"It looks like the order-C is being ignored and the C-contiguous checks fails when using `dpnp.asnumpy()`. Please refer to the below reproducer and output with dpnp+dpctl \u0026 cupy, more specifically `3c` section of the output.\n\nUpon a quick peek, much of the `asnumpy` is being forwarded to `dpt.__copy_utils__` and so opened an issue here. Apologies if this is not the right repo and should move it to DPNP.\n\nReproducer:\n```python\nimport numpy as np\nimport dpnp as dp\n\nprint(\"dpnp version:\", getattr(dp, \"__version__\", \"unknown\"))\n\n# Build the same data as in the larger code\nctr_offsets_slice = [\n    dp.array([0, 0, 0], dtype=np.int32),\n    dp.array([3, 3, 3], dtype=np.int32),\n    dp.array([5, 5, 5], dtype=np.int32),\n    dp.array([7, 7, 7], dtype=np.int32),\n    dp.array([10, 10, 10], dtype=np.int32),\n    dp.array([11, 11, 11], dtype=np.int32),\n    dp.array([12, 12, 12], dtype=np.int32),\n]\n\n# 3a: stack -\u003e dpnp_array (should be C-contiguous)\ntemp1 = dp.stack(ctr_offsets_slice)\n\n# 3b: transpose -\u003e dpnp_array view (not C-contiguous)\ntemp2 = dp.stack(ctr_offsets_slice).T\n\n# 3c: device-\u003ehost with \"order='C'\"\n# EXPECTED (per docstring \"works exactly like numpy.asarray\"): C-contiguous NumPy array\n# ACTUAL: order is ignored for dpnp_array, result keeps non-C layout\ntemp3 = dp.asnumpy(temp2, order='C')\n\nprint(\"3a. Testing : temp1: \", bool(temp1.flags['C_CONTIGUOUS']), type(temp1), len(temp1), temp1)\nprint(\"3b. Testing : temp2: \", bool(temp2.flags['C_CONTIGUOUS']), type(temp2), len(temp2), temp2)\nprint(\"3c. Testing : temp3: \", bool(temp3.flags['C_CONTIGUOUS']), type(temp3), len(temp3), temp3)\n\n# Programmatic check to make the failure obvious:\nif not temp3.flags['C_CONTIGUOUS']:\n    print(\"\\nBUG: dpnp.asnumpy(dpnp_array, order='C') returned a non-C-contiguous NumPy array.\")\n    print(\"     strides:\", temp3.strides, \"| shape:\", temp3.shape)\n\n```\n \nOutput from DPNP+DPCTL:\n```bash\ndpnp version: 0.19.0dev3+8.gac795ab9.dirty\n3a. Testing : temp1:  True \u003cclass 'dpnp.dpnp_array.dpnp_array'\u003e 7 [[ 0  0  0]\n [ 3  3  3]\n [ 5  5  5]\n [ 7  7  7]\n [10 10 10]\n [11 11 11]\n [12 12 12]]\n3b. Testing : temp2:  False \u003cclass 'dpnp.dpnp_array.dpnp_array'\u003e 3 [[ 0  3  5  7 10 11 12]\n [ 0  3  5  7 10 11 12]\n [ 0  3  5  7 10 11 12]]\n3c. Testing : temp3:  False \u003cclass 'numpy.ndarray'\u003e 3 [[ 0  3  5  7 10 11 12]\n [ 0  3  5  7 10 11 12]\n [ 0  3  5  7 10 11 12]]\n\nBUG: dpnp.asnumpy(dpnp_array, order='C') returned a non-C-contiguous NumPy array.\n     strides: (4, 12) | shape: (3, 7)\n```\n\nOutput from CUPY\n```bash\ncupy version: 13.4.1\n3a. Testing : temp1:  True \u003cclass 'cupy.ndarray'\u003e 7 [[ 0  0  0]\n [ 3  3  3]\n [ 5  5  5]\n [ 7  7  7]\n [10 10 10]\n [11 11 11]\n [12 12 12]]\n3b. Testing : temp2:  False \u003cclass 'cupy.ndarray'\u003e 3 [[ 0  3  5  7 10 11 12]\n [ 0  3  5  7 10 11 12]\n [ 0  3  5  7 10 11 12]]\n3c. Testing : temp3:  True \u003cclass 'numpy.ndarray'\u003e 3 [[ 0  3  5  7 10 11 12]\n [ 0  3  5  7 10 11 12]\n [ 0  3  5  7 10 11 12]]\n```","author":{"url":"https://github.com/abagusetty","@type":"Person","name":"abagusetty"},"datePublished":"2025-08-25T15:43:45.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/2138/dpctl/issues/2138"}