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#!/usr/bin/env python
"""
Plot histogram from list of dates
Usage
=====
Feed newline separated unix time via STDIN.
Ex.1: plot repository activity::
hg log --template '{date}\\n' | datehist.py -t `hg root`
git log --format='%at' | datehist.py -t `git rev-parse --show-toplevel`
"""
import sys
import datetime
import numpy
from matplotlib import pyplot
from matplotlib.dates import YearLocator, MonthLocator, DateFormatter
from matplotlib.dates import epoch2num, date2num
def num_now():
"""
Return the current date in matplotlib representation
"""
return date2num(datetime.datetime.now())
def get_limit(past):
"""
Get the date `past` time ago as the matplotlib representation
"""
return num_now() - float(past) * 365
def read_dates(limit, stream=sys.stdin):
"""
Read newline-separated unix time from stream
"""
dates = []
for line in stream:
num = epoch2num(float(line.strip()))
dates.append(num)
if num < limit:
break
stream.close()
return dates
def plot_datehist(dates, bins, title=None):
(hist, bin_edges) = numpy.histogram(dates, bins)
width = bin_edges[1] - bin_edges[0]
fig = pyplot.figure()
ax = fig.add_subplot(111)
ax.bar(bin_edges[:-1], hist / width, width=width)
ax.set_xlim(bin_edges[0], num_now())
ax.set_ylabel('Events [1/day]')
if title:
ax.set_title(title)
# set x-ticks in date
# see: http://matplotlib.sourceforge.net/examples/api/date_demo.html
ax.xaxis.set_major_locator(YearLocator())
ax.xaxis.set_major_formatter(DateFormatter('%Y'))
ax.xaxis.set_minor_locator(MonthLocator())
# format the coords message box
ax.format_xdata = DateFormatter('%Y-%m-%d')
ax.grid(True)
fig.autofmt_xdate()
return fig
def main():
from optparse import OptionParser
parser = OptionParser(usage='PRINT_UNIX_TIME | %prog [options]')
parser.add_option("-p", "--past", default="3",
help="how many years to plot histogram. (default: 3)")
parser.add_option("-o", "--out", default=None,
help="output file. open gui if not specified.")
parser.add_option("-b", "--bins", default=50, type=int,
help="number of bins for histogram. (default: 50)")
parser.add_option("-t", "--title")
parser.add_option("-d", "--doc", default=False, action="store_true",
help="print document")
(opts, args) = parser.parse_args()
if opts.doc:
print __doc__
return
dates = read_dates(get_limit(opts.past))
fig = plot_datehist(dates, opts.bins, title=opts.title)
if opts.out:
fig.savefig(opts.out)
else:
pyplot.show()
if __name__ == '__main__':
main()
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