matplotlib：如何从日期时间值的 cdf 图中删除垂直线

Question

以下代码绘制日期时间值的 cdf：

import matplotlib.pyplot as plt
import matplotlib.dates as dates
import numpy as np; np.random.seed(42)
import pandas as pd

objDate = dates.num2date(np.random.normal(735700, 300, 700))

ser = pd.Series(objDate)
ax = ser.hist(cumulative=True, density=1, bins=500, histtype='step')

plt.show()

如何去掉图表最右端的竖线？提到的方法不能作为将第 9 行替换为：

ax = ser.hist(cumulative=True, density=1, bins=sorted(objDate)+[np.inf], histtype='step')

给予

TypeError: can't compare datetime.datetime to float

Answer 1

CDF 实际上绘制为多边形，在 matplotlib 中由路径定义。路径又由顶点（去哪里）和代码（如何到达那里）定义。文档说我们不应该直接改变这些属性，但我们可以从满足我们需要的旧多边形派生出新多边形。

poly = ax.findobj(plt.Polygon)[0]
vertices = poly.get_path().vertices

# Keep everything above y == 0. You can define this mask however
# you need, if you want to be more careful in your selection.
keep = vertices[:, 1] > 0

# Construct new polygon from these "good" vertices
new_poly = plt.Polygon(vertices[keep], closed=False, fill=False,
                       edgecolor=poly.get_edgecolor(),
                       linewidth=poly.get_linewidth())
poly.set_visible(False)
ax.add_artist(new_poly)
plt.draw()

你应该得到如下图所示的结果：

matplotlib：如何从日期时间值的 cdf 图中删除垂直线

matplotlib: how to remove vertical line from cdf graph for datetime values

python

matplotlib

cdf