numpy.rollaxis — NumPy v1.15 Manual (original) (raw)
numpy. rollaxis(a, axis, start=0)[source]¶
Roll the specified axis backwards, until it lies in a given position.
This function continues to be supported for backward compatibility, but you should prefer moveaxis. The moveaxis function was added in NumPy 1.11.
| Parameters: | a : ndarray Input array. axis : int The axis to roll backwards. The positions of the other axes do not change relative to one another. start : int, optional The axis is rolled until it lies before this position. The default, 0, results in a “complete” roll. |
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| Returns: | res : ndarray For NumPy >= 1.10.0 a view of a is always returned. For earlier NumPy versions a view of a is returned only if the order of the axes is changed, otherwise the input array is returned. |
See also
Move array axes to new positions.
Roll the elements of an array by a number of positions along a given axis.
Examples
a = np.ones((3,4,5,6)) np.rollaxis(a, 3, 1).shape (3, 6, 4, 5) np.rollaxis(a, 2).shape (5, 3, 4, 6) np.rollaxis(a, 1, 4).shape (3, 5, 6, 4)