Previous topic

numpy.roll

Next topic

Binary operations

numpy.rot90

numpy.rot90(m, k=1, axes=(0, 1))[source]

Rotate an array by 90 degrees in the plane specified by axes.

Rotation direction is from the first towards the second axis.

Parameters:

m : array_like

Array of two or more dimensions.

k : integer

Number of times the array is rotated by 90 degrees.

axes: (2,) array_like

The array is rotated in the plane defined by the axes. Axes must be different.

New in version 1.12.0.

Returns:

y : ndarray

A rotated view of m.

See also

flip
Reverse the order of elements in an array along the given axis.
fliplr
Flip an array horizontally.
flipud
Flip an array vertically.

Notes

rot90(m, k=1, axes=(1,0)) is the reverse of rot90(m, k=1, axes=(0,1)) rot90(m, k=1, axes=(1,0)) is equivalent to rot90(m, k=-1, axes=(0,1))

Examples

>>> m = np.array([[1,2],[3,4]], int)
>>> m
array([[1, 2],
       [3, 4]])
>>> np.rot90(m)
array([[2, 4],
       [1, 3]])
>>> np.rot90(m, 2)
array([[4, 3],
       [2, 1]])
>>> m = np.arange(8).reshape((2,2,2))
>>> np.rot90(m, 1, (1,2))
array([[[1, 3],
        [0, 2]],
[[5, 7],
[4, 6]]])