Catch matplotlib warning

Question

I have a code (shown below as a minimal working example, MWE) which produces a warning when plotting a colorbar:

/usr/local/lib/python2.7/dist-packages/matplotlib/figure.py:1533: UserWarning: This figure includes Axes that are not compatible with tight_layout, so its results might be incorrect.
  warnings.warn("This figure includes Axes that are not "

I want to catch this warning so it is not displayed.

I know I should apply something along the lines of what is stated in this question How do I catch a numpy warning like it's an exception (not just for testing)?, but I'm not sure how to do it.

Here's the MWE:

import matplotlib.pyplot as plt 
import numpy as np
import matplotlib.gridspec as gridspec

x = np.random.randn(60) 
y = np.random.randn(60)
z = [np.random.random() for _ in range(60)]

fig = plt.figure()
gs = gridspec.GridSpec(1, 2)

ax0 = plt.subplot(gs[0, 0])
plt.scatter(x, y, s=20)

ax1 = plt.subplot(gs[0, 1])
cm = plt.cm.get_cmap('RdYlBu_r')
plt.scatter(x, y, s=20 ,c=z, cmap=cm)
cbaxes = fig.add_axes([0.6, 0.12, 0.1, 0.02]) 
plt.colorbar(cax=cbaxes, ticks=[0.,1], orientation='horizontal')

fig.tight_layout()
plt.show()

Answer 1

You probably don't want to catch this warning as an exception. That will interrupt the function call.

Use the warnings standard library module to control warnings.

You can suppress a warning from a specific function call using a context manager:

import warnings
with warnings.catch_warnings():
    warnings.simplefilter("ignore")
    fig.tight_layout()

---

To ignore all warnings from matplotlib:

warnings.filterwarnings("ignore", module="matplotlib")

---

To ignore only UserWarnings from matplotlib:

warnings.filterwarnings("ignore", category=UserWarning, module="matplotlib")

Answer 2

The printing of warning messages is done by calling showwarning(), which may be overridden; the default implementation of this function formats the message by calling formatwarning(), which is also available for use by custom implementations.

Override the showwarning() method to do nothing when the warning is issued. The function has the message and category of the warning available to it when called, so you can check and only hide the warnings from matplotlib.

Source: http://docs.python.org/2/library/warnings.html#warnings.showwarning