gantt.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import datetime as dt
import numpy
import matplotlib
import matplotlib.pyplot as plt
import matplotlib.dates as md
import locale
from functools import reduce
locale.setlocale(locale.LC_ALL, "")
matplotlib.rcParams['font.family']='sans'


today = '2014-01-01'
#task pl_start   pl_end     ac_start   ac_end     progress
data = """
A     2012-11-01 2012-12-31 2012-11-01 2012-12-31 1
B     2013-01-01 2013-03-14 2013-01-01 2013-03-14 1
C     2013-03-15 2014-04-30 2013-03-15 -          .7
D     2013-05-01 2013-06-30 2013-05-01 2013-06-30 1
E     2013-07-01 2013-08-31 2013-07-01 2013-08-31 1
F1    2013-09-01 2013-10-31 2013-09-01 2013-10-31 1
F2    2013-09-01 2014-01-17 2013-09-01 -          .8
F3    2013-09-01 2014-01-30 2013-09-01 -          .8
F4    2013-09-01 2014-03-31 2013-09-01 -          .6
G1    2013-11-01 2013-11-27 2013-11-01 2013-11-27 1
G2    2013-11-01 2014-01-17 2013-11-01 -          .8
L     2013-11-28 2013-12-19 2013-11-28 -          0
M     2013-11-28 2014-01-17 2013-11-28 -          .6
N     2013-12-04 2014-03-02 2013-12-04 -          .3
O     2013-12-20 2014-01-17 2013-12-20 -          .3
P     2013-12-20 2014-02-16 2013-12-20 -          .2
Q     2014-01-05 2014-01-13 2013-12-25 -          1
R     2014-01-18 2014-01-30 2013-12-18 -          .5
S     2014-01-31 2014-03-31 -          -          0
T     2014-03-01 2014-04-28 -          -          0
"""

datefmt = "%Y-%m-%d"
today = dt.datetime.strptime(today, datefmt)

data = [x.split() for x in data.split('\n')]
data = [x for x in data if len(x) == 6]
data = [{
    'label': x[0],
    'planned_start': dt.datetime.strptime(x[1], datefmt),
    'planned_end': dt.datetime.strptime(x[2], datefmt) + dt.timedelta(1),
    'actual_start': today if x[3] == '-' else
                    dt.datetime.strptime(x[3], datefmt),
    'actual_end': today if x[4] == '-' else
                  dt.datetime.strptime(x[4], datefmt) + dt.timedelta(1),
    'progress': float(x[5]),
    } for x in data]
for x in data:
    s = x['planned_start']
    e = x['planned_end']
    r = x['progress']
    x.update(progress_date=s+(e-s)*r)
for x in data:
    s = x['actual_start']
    e = x['actual_end']
    x.update(actual_end=e if e > s else s)

fig, ax = plt.subplots()
ax.hlines(
  [x - 0.2 for x in range(len(data))],
  [x['planned_start'] for x in data],
  [x['planned_end'] for x in data],
  linewidth=3, color='black', label='plan')
ax.hlines(
  [x for x in range(len(data))],
  [x['planned_start'] for x in data],
  [x['progress_date'] for x in data],
  linewidth=3, color='blue', label='Progress')
ax.hlines(
  [x + 0.2 for x in range(len(data))],
  [x['actual_start'] for x in data],
  [x['actual_end'] for x in data],
  linewidth=3, color='red', label='Performance')

def is_lightening(x, today):
    p = x['progress']
    return p > 0 and p < 1 \
        or p > 0 and x['progress_date'] > today \
        or p < 1 and x['progress_date'] < today
lightening = [
  [(today, idx - 0.5), (today, idx - 0.3),
   (x['progress_date'] if is_lightening(x, today) else today, idx),
   (today, idx + 0.3), (today, idx + 0.5)]
  for idx, x in enumerate(data)]
lightening = reduce(lambda x, y: x + y, lightening)
ax.plot(
  [x[0] for x in lightening],
  [x[1] for x in lightening],
  linewidth=1, color='blue')

ax.xaxis.set_major_formatter(md.DateFormatter('%Y-%m'))
ax.xaxis.set_major_locator(md.MonthLocator())
ax.xaxis.set_minor_locator(md.WeekdayLocator(byweekday=md.MO))
ax.xaxis.grid(b=True)

ax.yaxis.set_ticklabels([x['label'] for x in data])
ax.yaxis.set_ticks([idx for idx, x in enumerate(data)])
ax.yaxis.grid(b=True)
ax.set_ylim(len(data), -1)

ax.legend(loc='lower left')

fig.autofmt_xdate()

plt.show()