something like plt.matshow but with triangles

Question

Basically, I\'d like to make something like the following (triangles not squares as is typically used with plt.matshow).

One could start with four 2D arrays, each

Answer 1

See the example matplotlib.pyplot.tripcolor(*args, **kwargs) in the matplotlib documentation here. Here is a simplyfied version of want you need:

import matplotlib.pyplot as plt
import numpy as np

xy = np.asarray([
    [-0.01, 0.872], [-0.080, 0.883], [-0.069, 0.888], [-0.054, 0.890]])

x = xy[:, 0]*180/3.14159
y = xy[:, 1]*180/3.14159

triangles = np.asarray([[3, 2,  0]  , [3,  1, 2],   [ 0, 2,  1] , 
                        [0,  1, 2]])

xmid = x[triangles].mean(axis=1)
ymid = y[triangles].mean(axis=1)
x0 = -5
y0 = 52
zfaces = np.exp(-0.01*((xmid - x0)*(xmid - x0) + 
                (ymid - y0)*(ymid - y0)))


plt.figure()
plt.gca().set_aspect('equal')
plt.tripcolor(x, y, triangles, facecolors=zfaces, edgecolors='k')
plt.colorbar()
plt.title('tripcolor of user-specified triangulation')
plt.xlabel('Longitude (degrees)')
plt.ylabel('Latitude (degrees)')

plt.show()

You should get the following picture: