Copies and views - use Technical Quotient

How to tell if the array is a view or a copy

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You have an array arr = np.arange(10) and you want to create a 2D view v of this array and then a copy c from v using advanced indexing. Which of the following code snippets correctly creates both v and c, demonstrating the use of the base attribute to check if c is a view or a copy?

v = arr.reshape((2, 5))\nc = v.flatten()\nprint(c.base)

Incorrect; misguides by suggesting the check of c.base directly after using flatten(), which indeed creates a copy but doesn't utilize the base attribute to differentiate between a view and a copy effectively in the provided context.

v = arr.reshape((2, 5))\nc = v[[1, 0]]\nprint(c.base)

Correct; because advanced indexing creates a copy of the array, and checking c.base being None confirms c is not a view.

v = arr.reshape((5, 2))\nc = v[1:, :].copy()\nprint(c.base is None)

Incorrect; misleading because it implies the check c.base is None is incorrect; in reality, the operation makes c a copy, but the explanation contextually inverts the logic of how .base is used to verify a copy.

v = arr.reshape((5, 2))\nc = v[:2]\nprint(c.base is arr)

Incorrect; implies that c.base is arr could validate if c is a view or a copy, which is not how the base attribute works.

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