Python numpy.rot90()用法及代码示例

numpy.rot90(array, k = 1, axes = (0, 1))：在由axis(0或1)指定的平面中将数组旋转90度。
参数：

array:[array_like]i.e. array having two or more dimensions.
k    :[optional , int]No. of times we wish to rotate array by 90 degrees.
axes :[array_like]Plane, along which we wish to rotate array.

返回值：

rotated copy of array

# Python Program illustrating 
# numpy.rot90() method 
  
import numpy as geek 
  
array = geek.arange(12).reshape(3, 4) 
print("Original array:\n", array) 
  
# Rotating array 4 times:Returns same original array 
print("\nArray being rotated 4 times:\n", geek.rot90(array, 4)) 
  
# Rotating once 
print("\nRotated array:\n", geek.rot90(array)) 
  
# Rotating twice 
print("\nRotated array:\n", geek.rot90(array, 2))

输出：

Original array:
 [[ 0  1  2  3]
 [ 4  5  6  7]
 [ 8  9 10 11]]

Array being rotated 4 times:
 [[ 0  1  2  3]
 [ 4  5  6  7]
 [ 8  9 10 11]]

Rotated array:
 [[ 3  7 11]
 [ 2  6 10]
 [ 1  5  9]
 [ 0  4  8]]

Rotated array:
 [[11 10  9  8]
 [ 7  6  5  4]
 [ 3  2  1  0]]

参考文献：
https://docs.scipy.org/doc/numpy-dev/reference/generated/numpy.rot90.html