#!/usr/bin/env python
import sys
from simpleSVG import *
infilename='lorenz.dat'
inf=open(infilename,'r')
n=0
a=svg_class(fname="butterfly.svg")
a.scale(xmin=-15,xmax=15,ymin=0,ymax=30)
a.group(fill="black")
a.xaxis(dx=5)
a.yaxis(dy=5)
a.group(stroke_width=.1)
sys.stdout.write("reading lines from lorenz.dat\n")
while 1:
	aline=inf.readline()
	if not aline: break
	if aline[0]=='#': continue
	t,x,y,z=[float(x) for x in aline.split()]
	s=.2*y
	red =max(0.,min(1.,.5+s))
	green =0.
	blue=max(0.,min(1.,.5-s))
	if n==0:
		xl,zl=x,z
		n=n+1
		continue
	segmentcolor=rgbstring(red,green,blue)
	a.draw(xl,zl,x,z,stroke=segmentcolor) 
	xl,zl=x,z
	n=n+1
a.group()
a.group(stroke_width=.3,fill='black')
a.text(.3j,.10j,0.,'Lorenz attractor',font_size="24pt")
a.group(font_size="24pt")
a.text(.02j,.43j,0.,'z')
a.text(.5j,.98j,0.,'x')
a.close()
