stack(arrays, axis=0, out=None)¶
Join a sequence of arrays along a new axis.
axis parameter specifies the index of the new axis in the
dimensions of the result. For example, if
axis=0 it will be the first
dimension and if
axis=-1 it will be the last dimension.
New in version 1.10.0.
Each array must have the same shape.
The axis in the result array along which the input arrays are stacked.
If provided, the destination to place the result. The shape must be correct, matching that of what stack would have returned if no out argument were specified.
The stacked array has one more dimension than the input arrays.
>>> arrays = [np.random.randn(3, 4) for _ in range(10)] >>> np.stack(arrays, axis=0).shape (10, 3, 4)
>>> np.stack(arrays, axis=1).shape (3, 10, 4)
>>> np.stack(arrays, axis=2).shape (3, 4, 10)
>>> a = np.array([1, 2, 3]) >>> b = np.array([2, 3, 4]) >>> np.stack((a, b)) array([[1, 2, 3], [2, 3, 4]])
>>> np.stack((a, b), axis=-1) array([[1, 2], [2, 3], [3, 4]])