Hinton diagram on a football pitch

hinton.py

import numpy as n
import pylab as p
from matplotlib.patches import Rectangle
from matplotlib.collections import PatchCollection

from pitch import create_normalized_pitch


def _add_centered_square(xy, area):
    size = n.sqrt(area)
    loc = n.asarray(xy) - size/2.0
    return Rectangle(loc, size, size)


def hinton(a, ax=None):
    if ax is None:
        ax = p.gca()
    patches = []
    colors = []
    for xy, val in n.ndenumerate(a):
        colors.append(val)
        patches.append(_add_centered_square(n.asarray(xy) + 0.5, abs(val)))
    patch_coll = PatchCollection(patches, cmap=p.get_cmap('plasma'), alpha=0.6)
    patch_coll.set_array(n.array(colors))
    ax.add_collection(patch_coll)
    ax.autoscale_view()


if __name__ == '__main__':
    figure, axes = create_normalized_pitch(pcolor='white')
    a = n.random.normal(loc=0.0, scale=0.2, size=(100, 100))
    hinton(a, ax=axes)
    figure.show()