Python matplotlib imshow

将一个二维数组显示为图片

import numpy as np
import matplotlib.pyplot as plt

fig = plt.figure()
data = np.linspace(0, 1, 40000).reshape(-1, 200)
ax1 = fig.add_subplot(3, 2, 1)
ax1.imshow(data)

ax2 = fig.add_subplot(3, 2, 2)
# show all the color map style: plt.colormaps()
ax2.imshow(data, cmap='hot')

ax3 = fig.add_subplot(3, 2, 3)
# origin default is upper left
ax3.imshow(data, origin='lower', cmap='hot')

ax4 = fig.add_subplot(3, 2, 4)
# scale the coordinates
ax4.imshow(data, cmap='hot', extent=(10, 20, 0, 10))

plt.show()

图1使用默认设置，图2自定义了颜色映射，图三将数组的元素从左下角开始放，图4缩放了坐标轴。