I contributed to the matplotlib enhancement proposal 12, which proposed reorganizing the examples gallery to make it easier for matplotlib users to find relevant examples.

Part of the problem was that there were old pylab examples, but the new pyplot API was now preferred over the old pylab API (which was really present mostly to convert MATLAB users). I helped fix all the pylab examples by changing

from pylab import *

statements to explicit

import matplotlib.pyplot as plt
import numpy as np

Pull requests