git_commit_dates.py

import numpy as np
import matplotlib.pyplot as plt

###########################################################
# dates.txt is created by `git log | grep Date > dates.txt`
###########################################################
hours = []
with open("dates.txt") as f:
    for line in f:
        hours.append( int(line.rstrip().split()[4].split(":")[0]) )
        
fig, ax = plt.subplots(1,1)
fig.set_figwidth(10)
fig.set_figheight(6)
ax.grid(axis='x')
ax.set_xticks(np.arange(0,24))
ax.set_xticklabels(np.arange(0,24), rotation=45)
ax.hist(hours, bins=24)
ax.set_xlabel('hour of the day (0-23)')
ax.set_ylabel('freq')
ax.set_title('Histogram of commits by hour of the day')