.. _api-scatter_piecharts:

api example code: scatter_piecharts.py
======================================



.. plot:: /home/tcaswell/source/p/matplotlib/doc/mpl_examples/api/scatter_piecharts.py

::

    """
    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))
    s1 = max(max(x), max(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))
    s2 = max(max(x), max(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))
    s3 = max(max(x), max(y))
    
    fig, ax = plt.subplots()
    ax.scatter(np.arange(3), np.arange(3), marker=(xy1, 0),
               s=[s1*s1*_ for _ in sizes], facecolor='blue')
    ax.scatter(np.arange(3), np.arange(3), marker=(xy2, 0),
               s=[s2*s2*_ for _ in sizes], facecolor='green')
    ax.scatter(np.arange(3), np.arange(3), marker=(xy3, 0),
               s=[s3*s3*_ for _ in sizes], facecolor='red')
    
    plt.show()
    

Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)