Path Tutorial

Defining paths in your Matplotlib visualization.

The object underlying all of the matplotlib.patches objects is the Path, which supports the standard set of moveto, lineto, curveto commands to draw simple and compound outlines consisting of line segments and splines. The Path is instantiated with a (N, 2) array of (x, y) vertices, and an N-length array of path codes. For example to draw the unit rectangle from (0, 0) to (1, 1), we could use this code:

import numpy as np

import matplotlib.pyplot as plt

import matplotlib.patches as patches
from matplotlib.path import Path

verts = [
   (0., 0.),  # left, bottom
   (0., 1.),  # left, top
   (1., 1.),  # right, top
   (1., 0.),  # right, bottom
   (0., 0.),  # ignored
]

codes = [
    Path.MOVETO,
    Path.LINETO,
    Path.LINETO,
    Path.LINETO,
    Path.CLOSEPOLY,
]

path = Path(verts, codes)

fig, ax = plt.subplots()
patch = patches.PathPatch(path, facecolor='orange', lw=2)
ax.add_patch(patch)
ax.set_xlim(-2, 2)
ax.set_ylim(-2, 2)
plt.show()