Lines with a ticked patheffect

Ticks can be added along a line to mark one side as a barrier using TickedStroke. You can control the angle, spacing, and length of the ticks.

The ticks will also appear appropriately in the legend.

import numpy as np
import matplotlib.pyplot as plt
from matplotlib import patheffects

# Plot a straight diagonal line with ticked style path
fig, ax = plt.subplots(figsize=(6, 6))
ax.plot([0, 1], [0, 1], label="Line",
        path_effects=[patheffects.withTickedStroke(spacing=7, angle=135)])

# Plot a curved line with ticked style path
nx = 101
x = np.linspace(0.0, 1.0, nx)
y = 0.3*np.sin(x*8) + 0.4
ax.plot(x, y, label="Curve", path_effects=[patheffects.withTickedStroke()])

ax.legend()

plt.show()