relative_difference.py

#!/usr/bin/env python

import numpy as np
from matplotlib import cm
from matplotlib import pyplot as plt


xs, ys = np.meshgrid(
    np.linspace(1/1000, 1, 999),
    np.linspace(1/1000, 1, 999),
)

zs = []
for x, y in zip(xs.ravel(), ys.ravel()):
    z = (x - y) / (x + y)
    zs.append(z)
zs = np.array(zs).reshape(xs.shape)

fig = plt.figure(figsize=(24, 24))
ax = plt.axes(projection='3d')
ax.plot_surface(xs, ys, zs, cmap=cm.coolwarm_r)
ax.set_xlabel('First')
ax.set_ylabel('Second')
ax.set_zlabel('Difference')
ax.view_init(30, 220)
plt.savefig('3d.png')
plt.show()