Shangri-La Diet Chart

Here's the complete code, you need pylab (i.e. matplotlib) to draw the graph.
# -*- coding: iso-8859-1 -*-<br /><br />from pylab import *<br />from datetime import date<br /><br />import os<br />import csv<br /><br /># Shangri-La diet at http://www.sethroberts.net/<br /><br />numDays = 50 # How many days ahead should we make the chart?<br />slope = 0.7/7.0 # 1 kilo a week = 1/7kg per day<br /><br />kg2lbs = 2.2046226218487757 # From frink calculator http://futureboy.homeip.net/frinkdocs/<br /><br />vals = []<br />for datestr, weight in csv.reader(open("myweight.csv")):<br /> year, mon, day = datestr.split('-')<br /><br /> vals.append((date(int(year), int(mon), int(day)), float(weight)))<br /><br />startDate, startWeight = vals[0] # Get starting info<br /><br /><br />days = [ (x[0] - startDate).days for x in vals ]<br />weights = [ x[1] for x in vals ]<br /><br />ideal_x = arange(0, numDays)<br />ideal_y = [ startWeight - (x * slope) for x in ideal_x ]<br /><br />(ar, br) = polyfit(days, weights, 1)<br />print "Least squares slope of %.2f kg/week or %.2f lbs/week" % (ar * 7, (ar * kg2lbs) * 7)<br />least_squares = polyval([ar, br], ideal_x)<br /><br />figure(figsize=(5.5, 3.5)) # Size it smaller for the web<br /><br /># Plot three curves<br />l1 = plot(days, weights, "ko", ideal_x, ideal_y, '--', ideal_x, least_squares, '-')<br />legend((u'Actual', u'Target', 'Least-squares fit'))<br />title('Weight over time')<br />xlabel('Days')<br />ylabel('Kg')<br /><br /># Copy the kg scale for later<br />kgYLim = ylim()[:]<br /><br /># Make a LBS scale on the right hand side<br />lbsWeight = [ x[1] * kg2lbs for x in vals ]<br />ax2 = twinx() # make a second axis<br />l2 = plot(days, lbsWeight, '.')<br />ylabel('LBS')<br /># Force the limits to be the same as Kg<br />ylim( kgYLim[0] * kg2lbs, kgYLim[1] * kg2lbs )<br />ax2.yaxis.tick_right() # plot on the right<br /><br /># Save as a png and show it too<br />lastDate = vals[-1][0].strftime("%Y-%m-%d")<br />fname = 'weight-%s.png' % (lastDate)<br />savefig(fname, dpi=72) # Tiny<br />saveTo = '/home2/forusers/webapps/tg/tg/static/images/'+fname<br />os.rename(fname, saveTo)<br />print "Saved to: %s" % (saveTo)<br /><br />show()<br /><br />After it saves the file locally, I use unison to synchronize with my website.