matplotlib subplots with shared axis

Question

I have some troubles understanding how the matplotlib subplots allow for sharing axis between them. I saw some exemples but i could not modify one to fit my use case..; Here i replaced my data by uniforms so the plots wont be interesting but whatever...

import numpy as np
import matplotlib.pyplot as plt
import matplotlib as mpl
from matplotlib import cm
d = 4
n1 = 100000
n2 = 100
background_data = np.random.uniform(size=(n1,d))
foreground_data = np.random.uniform(size=(n2,d))
fig = plt.figure()
for i in np.arange(d):
 for j in np.arange(d):
 if i != j:
 ax = fig.add_subplot(d,d,1+i*d+j)
 ax = plt.hist2d(background_data[:, i], background_data[:, j],
 bins=3*n2,
 cmap=cm.get_cmap('Greys'),
 norm=mpl.colors.LogNorm())
 ax = plt.plot(foreground_data[:,i],foreground_data[:,j],'o',markersize=0.2)

Q : How can i share the x and y axes for all plots ?

Answer 1

By far the easiest option is to use sharex and sharey arguments of plt.subplots.

import numpy as np
import matplotlib.pyplot as plt
import matplotlib as mpl
d = 4
n1 = 100000
n2 = 100
background_data = np.random.uniform(size=(n1,d))
foreground_data = np.random.uniform(size=(n2,d))
fig, axs = plt.subplots(d,d, sharex=True, sharey=True)
for i in np.arange(d):
 for j in np.arange(d):
 if i != j:
 ax = axs[j,i]
 ax.hist2d(background_data[:, i], background_data[:, j],
 bins=3*n2,
 cmap=plt.get_cmap('Greys'),
 norm=mpl.colors.LogNorm())
 ax.plot(foreground_data[:,i],foreground_data[:,j],'o',markersize=2)
 else:
 axs[j,i].remove()
fig.savefig("sharedaxes.png") 
plt.show()

Plot

• lrnv: This is perfect. Thanks a lot