Hi,

My graph is almost ready:
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from pyx import *

text.set(mode="latex")

g = graph.graphxy(width=20,
    x=graph.axis.lin(min=-28, max=28, title="$Log_2(SAGE-ratio)$"),
    x2=None,
    y=graph.axis.lin(min=-28, max=28, title="$Log_2(Q\_RT-PCR-ratio)$"),
    y2=None,
    key=graph.key.key(pos="br", dist=0.1)
)

g.plot(graph.data.file("explevels.dat ", x=1, y=2, text=3), [graph.style.symbol(), graph.style.text()])

g.plot(graph.data.function("x(y)=y", title=r"$x = y$"))

g.writeEPSfile("minimal")
g.writePDFfile("minimal")
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my only problem is that when I added the "key=graph.key.key(pos="br", dist=0.1)" to label my function, I get this error:
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python q_rt- pcr.py
Traceback (most recent call last):
  File "q_rt-pcr.py", line 17, in ?
    g.writeEPSfile("minimal")
  File "/usr/lib/python2.4/site-packages/pyx/canvas.py", line 329, in wrappedindocument
    return method(d, file)
  File "/usr/lib/python2.4/site-packages/pyx/document.py", line 155, in writeEPSfile
    pswriter.epswriter(self, file, *args, **kwargs)
  File "/usr/lib/python2.4/site-packages/pyx/pswriter.py", line 278, in __init__
    page.processPS(pagefile, self, acontext, registry, pagebbox)
  File "/usr/lib/python2.4/site-packages/pyx/document.py", line 138, in processPS
    self._process("processPS", *args)
  File "/usr/lib/python2.4/site-packages/pyx/document.py", line 81, in _process
    getattr(self.canvas, processMethod)(canvasfile, writer, context, registry, bbox)
  File "/usr/lib/python2.4/site-packages/pyx/graph/graph.py", line 157, in processPS
    self.finish()
  File "/usr/lib/python2.4/site-packages/pyx/graph/graph.py", line 252, in finish
    self.dokey()
  File "/usr/lib/python2.4/site-packages/pyx/graph/graph.py", line 483, in dokey
    c = self.key.paint(self.plotitems)
  File "/usr/lib/python2.4/site-packages/pyx/graph/key.py", line 106, in paint
    subc = self.paintcolumn(plotitems[:itemspercolumn])
  File "/usr/lib/python2.4/site-packages/pyx/graph/key.py", line 92, in paintcolumn
    titlebox.plotitem.key_pt(c, 0, y_pt, self.symbolwidth_pt, self.symbolheight_pt)
  File "/usr/lib/python2.4/site-packages/pyx/graph/graph.py", line 111, in key_pt
    style.key_pt(privatedata, self.sharedata, graph, x_pt, y_pt, width_pt, height_pt)
  File "/usr/lib/python2.4/site-packages/pyx/graph/style.py", line 742, in key_pt
    raise RuntimeError("Style currently doesn't provide a graph key")
RuntimeError: Style currently doesn't provide a graph key
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Now what's wrong? I just used the same code line as in this example: http://pyx.sourceforge.net/examples/graphs/change.html

Bye,

carl