How to plot this figure?

Question

I'd like to plot something like above plot using python. There is one feature I like:

The figure is divided into several rectangles with different color (and number). the only approximate plot I can think is scatter plot. But a scatter plot present some points, not rectangles.

Can anyone help me?

Answer 1

The answer probably depends on what kind of data you want to show. There are several ways to produce such a plot,

1. Using Rectangles with given vertices
2. Using imshow of an array on an equally spaced grid
3. Using pcolormesh of an array on an unequally spaced grid

Assuming that you want to plot a histogram and chosing the third option, a possible solution may look something like this (based on a histogram2d)

import matplotlib.pyplot as plt
import numpy as np

xedges = [0, 1, 1.5, 3, 5]
yedges = [0, 2, 3, 4, 6]

# produce histogram
x = np.random.normal(2.5, 1, 100)
y = np.random.normal(1.5, 1, 100)
H, xedges, yedges = np.histogram2d(y, x, bins=(xedges, yedges))

fig=plt.figure()
ax = fig.add_subplot(111)
ax.set_title('Something')
X, Y = np.meshgrid(xedges, yedges)
im = ax.pcolormesh(X, Y, H)

# label the histogram bins
for i in range(len(yedges)-1):
    for j in range(len(xedges)-1):
        ax.text( (xedges[j+1]-xedges[j])/2.+xedges[j] , 
                 (yedges[i+1]-yedges[i])/2.+yedges[i] , 
                str(H[i, j]) , ha="center", va="center", color="w", fontweight="bold")
plt.colorbar(im)        

plt.show()