inpolygon for Python - Examples of matplotlib.path.Path contains_points() method?

Question

I have been searching for a python alternative to MATLAB\'s inpolygon() and I have come across contains_points as a good option.

However, the docs are a little bare with

Answer 1

I wrote this function to return a array as in matlab inpolygon function. But this will return only the points that are inside the given polygon. You can't find the points in the edge of the polygon with this function.

import numpy as np
from matplotlib import path

def inpolygon(xq, yq, xv, yv):
    shape = xq.shape
    xq = xq.reshape(-1)
    yq = yq.reshape(-1)
    xv = xv.reshape(-1)
    yv = yv.reshape(-1)
    q = [(xq[i], yq[i]) for i in range(xq.shape[0])]
    p = path.Path([(xv[i], yv[i]) for i in range(xv.shape[0])])
    return p.contains_points(q).reshape(shape)

You can call the function as:

xv = np.array([0.5,0.2,1.0,0,0.8,0.5])
yv = np.array([1.0,0.1,0.7,0.7,0.1,1])
xq = np.array([0.1,0.5,0.9,0.2,0.4,0.5,0.5,0.9,0.6,0.8,0.7,0.2])
yq = np.array([0.4,0.6,0.9,0.7,0.3,0.8,0.2,0.4,0.4,0.6,0.2,0.6])
print(inpolygon(xq, yq, xv, yv))

As in the matlab documentation this function,

returns in indicating if the query points specified by xq and yq are inside or on the edge of the polygon area defined by xv and yv.