在plt.contourf中使用非线性级别时保持色彩映射表的线性颜色

import numpy as np
import matplotlib.pyplot as plt
import matplotlib.colors as colors

x = np.linspace(-5, 5, 100)
y = np.linspace(-5, 5, 100)
X, Y = np.meshgrid(x, y)
Z = np.sin(np.sqrt(X**2 + Y**2))
levels = np.linspace(-1, 1, 10)  # 非线性级别

norm = colors.Normalize(vmin=-1, vmax=1)  # 将数据映射到-1到1的范围内

plt.contourf(X, Y, Z, levels=levels, cmap='jet', norm=norm)
plt.colorbar()  # 添加颜色条
plt.show()