manual/graph.py

   1 #!/usr/bin/env python
   2 import sys
   3 sys.path.append("..")
   4 from pyx import *
   5 from pyx.graph import *
   6
   7 c = canvas.canvas()
   8 t = c.insert(tex.tex())
   9 g = c.insert(graphxy(t, width=10))
  10 g.plot(data("graph.dat", x=1, y=2))
  11 g.finish()
  12 c.writetofile("graph1")
  13
  14
  15 c = canvas.canvas()
  16 t = tex.tex()
  17
  18 a, b = 2, 9
  19
  20 mypainter=axispainter(baselineattrs=canvas.earrow.normal)
  21
  22 g = c.insert(graphxy(t, width=10, x2=None, y2=None,
  23                      x=linaxis(min=0, max=10,
  24                                part=manualpart(ticks=(frac(a, 1),
  25                                                       frac(b, 1)),
  26                                                texts=("a", "b")),
  27                                painter=mypainter),
  28                      y=linaxis(painter=mypainter, part=manualpart())))
  29
  30 line = g.plot(function("y=(x-3)*(x-5)*(x-7)"))
  31 g.finish()
  32
  33 pa = path.path(g.axes["x"].gridpath(a))
  34 pb = path.path(g.axes["x"].gridpath(b))
  35 (splita,), (splitpa,) = line.path.intersect(pa)
  36 (splitb,), (splitpb,) = line.path.intersect(pb)
  37 area = (pa.split(splitpa)[0] <<
  38         line.path.split(splita, splitb)[1] <<
  39         pb.split(splitpb)[0].reversed())
  40 area.append(path.closepath())
  41 g.stroke(area, canvas.linewidth.THick, canvas.filled(color.gray(0.8)))
  42 t.text(g.pos(0.5*(a+b), 0)[0], 1, r"\int_a^b f(x) {\rm d}x", tex.halign.center, tex.style.math)
  43
  44 c.insert(t)
  45 c.writetofile("graph2")