由于对称性，实际上只需要计算图像256*256的四分之一，即64*64，然后将其逐块旋转90度，然后将它们组合起来。这样，总时间是计算256×256像素的1/4倍。在

以下是示例。在import numpy as np

import matplotlib.pyplot as plt

##Just calculate 64*64

arr = np.zeros((64,64,3), dtype=np.uint8)

imgsize = arr.shape[:2]

innerColor = (0, 0, 0)

outerColor = (255, 255, 255)

for y in range(imgsize[1]):

for x in range(imgsize[0]):

#Find the distance to the corner

distanceToCenter = np.sqrt((x) ** 2 + (y - imgsize[1]) ** 2)

#Make it on a scale from 0 to 1innerColor

distanceToCenter = distanceToCenter / (np.sqrt(2) * imgsize[0])

#Calculate r, g, and b values

r = outerColor[0] * distanceToCenter + innerColor[0] * (1 - distanceToCenter)

g = outerColor[1] * distanceToCenter + innerColor[1] * (1 - distanceToCenter)

b = outerColor[2] * distanceToCenter + innerColor[2] * (1 - distanceToCenter)

# print r, g, b

arr[y, x] = (int(r), int(g), int(b))

#rotate and combine

arr1=arr

arr2=arr[::-1,:,:]

arr3=arr[::-1,::-1,:]

arr4=arr[::,::-1,:]

arr5=np.vstack([arr1,arr2])

arr6=np.vstack([arr4,arr3])

arr7=np.hstack([arr6,arr5])

plt.imshow(arr7, cmap='gray')

plt.show()