绘图示例小插曲

使用 matplotlib 绘制图表并添加注释的示例。

import numpy as np
import matplotlib.pyplot as plt

n = 256
X = np.linspace(0, 2, n)
Y = np.sin(2 * np.pi * X)

plt.plot(X, Y, lw=2, color="violet")
plt.xlim(-0.2, 2.2)
plt.xticks([])
plt.ylim(-1.2, 1.2)
plt.yticks([])


# Add a title and a box around it
from matplotlib.patches import FancyBboxPatch

ax = plt.gca()
ax.add_patch(
    FancyBboxPatch(
        (-0.05, 0.87),
        width=0.66,
        height=0.165,
        clip_on=False,
        boxstyle="square,pad=0",
        zorder=3,
        facecolor="white",
        alpha=1.0,
        transform=plt.gca().transAxes,
    )
)

plt.text(
    -0.05,
    1.02,
    " Regular Plot:      plt.plot(...)\n",
    horizontalalignment="left",
    verticalalignment="top",
    size="xx-large",
    transform=plt.gca().transAxes,
)

plt.text(
    -0.05,
    1.01,
    "\n\n   Plot lines and/or markers ",
    horizontalalignment="left",
    verticalalignment="top",
    size="large",
    transform=plt.gca().transAxes,
)

plt.show()