"""

This example makes custom 'pie charts' as the markers for a scatter plotqu

Thanks to Manuel Metz for the example

"""

import math

import numpy as np

import matplotlib.pyplot as plt

# first define the ratios

r1 = 0.2 # 20%

r2 = r1 + 0.4 # 40%

# define some sizes of the scatter marker

sizes = [60, 80, 120]

# calculate the points of the first pie marker

#

# these are just the origin (0,0) +

# some points on a circle cos,sin

x = [0] + np.cos(np.linspace(0, 2*math.pi*r1, 10)).tolist()

y = [0] + np.sin(np.linspace(0, 2*math.pi*r1, 10)).tolist()

xy1 = list(zip(x, y))

# ...

x = [0] + np.cos(np.linspace(2*math.pi*r1, 2*math.pi*r2, 10)).tolist()

y = [0] + np.sin(np.linspace(2*math.pi*r1, 2*math.pi*r2, 10)).tolist()

xy2 = list(zip(x, y))

x = [0] + np.cos(np.linspace(2*math.pi*r2, 2*math.pi, 10)).tolist()

y = [0] + np.sin(np.linspace(2*math.pi*r2, 2*math.pi, 10)).tolist()

xy3 = list(zip(x, y))

fig, ax = plt.subplots()

d = np.arange(3)

ax.scatter(d, d, marker=(xy1, 0), s=sizes, facecolor='blue')

ax.scatter(d, d, marker=(xy2, 0), s=sizes, facecolor='green')

ax.scatter(d, d, marker=(xy3, 0), s=sizes, facecolor='red')

plt.show()