matplotlib-users Mailing List for matplotlib

Hi all,
I'd like to ask about some issues I am having with using matplotlib
with the latest wxpython version 2.9.1.1;
I already mentioned that on the wxpython list:
https://groups.google.com/forum/#!topic/wxpython-users/vG-5NJ4vXnc
but it is unclear whether this is a bug in wx or a possible problem
with the backend_wx which happened to be "tolerated" in wxpython
sofar.

Simple code using the WX backend seems to
work ok in 2.8.12.1 and 2.9.1.1 but not in 2.9.2.1.
The graph canvas is inactive and transparent - showing the
screen below this active frame; with resizing and moving this frame,
there are artefacts and display glitches and redrawing errors around
it, but the graph is not shown and there are no exceptions thrown.

(I am using Python 2.7.2, matplotlib 1.0.1; win 7 and Win XP; wxPython
32bit (unicode))



# # # # # # # # # # # pylab - wxPython  # # # # # # # # # # # # # # # # #

#! Python
# -*- coding: utf-8 -*-

import wxversion
# wxversion.select('2.8') # 2.8.12.1 ok
# wxversion.select('2.9.1') # 2.9.1.1 ok
wxversion.select('2.9.2') # 2.9.2.1     !! display errors in pylab

import wx

import matplotlib # http://matplotlib.sourceforge.net/

# matplotlib.use('WXAgg') # ok in both, wx 2.8 and 2.9.x
matplotlib.use('WX')

import pylab

pylab.plot(range(3), range(3), label="a")
pylab.show()

# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
A very simple version without pylab shows the same problem:
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #

#! Python
# -*- coding: utf-8 -*-

import wxversion
# wxversion.select('2.8')
wxversion.select('2.9.2')
import wx
import matplotlib
matplotlib.use('WX')
from matplotlib.backends.backend_wx import FigureCanvasWx as
FigureCanvas  # err on wx 2.9.2
# from matplotlib.backends.backend_wxagg import FigureCanvasWxAgg as
FigureCanvas # ok
from matplotlib.figure import Figure

class CanvasFrame(wx.Frame):
    def __init__(self, ):
        wx.Frame.__init__(self, None, -1, 'CanvasFrame', size=(550,350))
        self.figure = Figure()
        self.axes = self.figure.add_subplot(111)
        self.axes.plot(range(4),range(4))
        self.figure_canvas = FigureCanvas(self, -1, self.figure)
        self.sizer = wx.BoxSizer(wx.VERTICAL)
        self.sizer.Add(self.figure_canvas, 1, wx.LEFT | wx.TOP | wx.GROW)
        self.SetSizer(self.sizer)

if __name__=='__main__':
    app = wx.App(False)
    frm = CanvasFrame()
    frm.Show(True)
    app.MainLoop()

# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #

It is likely to depending on
matplotlib.backends.backend_wx :: FigureCanvasWx (or some inherited
classes), but I had sofar no success in finding the problematic code.

Could you maybe give any pointer where to look into, or maybe how to
activate some exception tracebacks etc? (Changing _DEBUG = 5 in
...\matplotlib\backends\backend_wx.py to other values doesn't seem to
have this effect).

Thanks in advance,
    vbr

I'd like to add a title to a RadioButton axis, but the usual title('xxx') seems to get ignored.  Can I do that?

 

This is an example:

 

raOVL   = axes([0.05, 0.1, 0.15, 0.15], axisbg=axcolor)

title   = 'Overlap'

radioOV = RadioButtons(raOVL, ['10%','30%','50%','70%'])

 

 

-Paul Blelloch

 

here is the sample code "embedding_in_gtk2.py"

 6 import gtk
 7
 8 from matplotlib.figure import Figure
 9 from numpy import arange, sin, pi
10
11 # uncomment to select /GTK/GTKAgg/GTKCairo
12 #from matplotlib.backends.backend_gtk import FigureCanvasGTK as FigureCanvas
13 from matplotlib.backends.backend_gtkagg import FigureCanvasGTKAgg
as FigureCanvas
14 #from matplotlib.backends.backend_gtkcairo import
FigureCanvasGTKCairo as FigureCanvas
15
16 # or NavigationToolbar for classic
17 #from matplotlib.backends.backend_gtk import NavigationToolbar2GTK
as NavigationToolbar
18 from matplotlib.backends.backend_gtkagg import
NavigationToolbar2GTKAgg as NavigationToolbar
19
20
21 win = gtk.Window()
22 win.connect("destroy", lambda x: gtk.main_quit())
23 win.set_default_size(400,300)
24 win.set_title("Embedding in GTK")
25
26 vbox = gtk.VBox()
27 win.add(vbox)
28
29 fig = Figure(figsize=(5,4), dpi=100)
30 import pudb
31 pudb.set_trace()
32 ax = fig.add_subplot(111)
33 t = arange(0.0,3.0,0.01)
34 s = sin(2*pi*t)
35
36 ax.plot(t,s)
37
38
39 canvas = FigureCanvas(fig)  # a gtk.DrawingArea
40 vbox.pack_start(canvas)
41 toolbar = NavigationToolbar(canvas, win)
42 vbox.pack_start(toolbar, False, False)
43
44
45 win.show_all()
46 gtk.main()

on line 36 error segfault.
Here is the gdb session

Starting program: /usr/bin/python2.7 embedding_in_gtk2.py
[Thread debugging using libthread_db enabled]

Program received signal SIGSEGV, Segmentation fault.
0x00007fffeda71594 in __cxa_allocate_exception () from
/usr/lib/gcc/x86_64-pc-linux-gnu/4.4.5/libstdc++.so.6
#0  0x00007fffeda71594 in __cxa_allocate_exception () from
/usr/lib/gcc/x86_64-pc-linux-gnu/4.4.5/libstdc++.so.6
#1  0x00007fffe4830164 in py_to_agg_transformation_matrix(_object*, bool) ()
   from /usr/lib64/python2.7/site-packages/matplotlib/_path.so
#2  0x00007fffe483addb in _path_module::update_path_extents(Py::Tuple const&) ()
   from /usr/lib64/python2.7/site-packages/matplotlib/_path.so
#3  0x00007fffe4841ad8 in
Py::ExtensionModule<_path_module>::invoke_method_varargs(void*,
Py::Tuple const&) ()
   from /usr/lib64/python2.7/site-packages/matplotlib/_path.so
#4  0x00007fffe482b54d in method_varargs_call_handler () from
/usr/lib64/python2.7/site-packages/matplotlib/_path.so
#5  0x00007ffff7b09a7b in PyEval_EvalFrameEx () from
/usr/lib64/libpython2.7.so.1.0
#6  0x00007ffff7b0b658 in PyEval_EvalCodeEx () from
/usr/lib64/libpython2.7.so.1.0
#7  0x00007ffff7b09bc7 in PyEval_EvalFrameEx () from
/usr/lib64/libpython2.7.so.1.0
#8  0x00007ffff7b0b658 in PyEval_EvalCodeEx () from
/usr/lib64/libpython2.7.so.1.0
#9  0x00007ffff7b09bc7 in PyEval_EvalFrameEx () from
/usr/lib64/libpython2.7.so.1.0
#10 0x00007ffff7b0b658 in PyEval_EvalCodeEx () from
/usr/lib64/libpython2.7.so.1.0
#11 0x00007ffff7b09bc7 in PyEval_EvalFrameEx () from
/usr/lib64/libpython2.7.so.1.0
#12 0x00007ffff7b0b658 in PyEval_EvalCodeEx () from
/usr/lib64/libpython2.7.so.1.0
#13 0x00007ffff7b09bc7 in PyEval_EvalFrameEx () from
/usr/lib64/libpython2.7.so.1.0
#14 0x00007ffff7b0b658 in PyEval_EvalCodeEx () from
/usr/lib64/libpython2.7.so.1.0
#15 0x00007ffff7b0b762 in PyEval_EvalCode () from /usr/lib64/libpython2.7.so.1.0
#16 0x00007ffff7b2545c in ?? () from /usr/lib64/libpython2.7.so.1.0
#17 0x00007ffff7b25530 in PyRun_FileExFlags () from
/usr/lib64/libpython2.7.so.1.0
#18 0x00007ffff7b26a1f in PyRun_SimpleFileExFlags () from
/usr/lib64/libpython2.7.so.1.0
#19 0x00007ffff7b377cc in Py_Main () from /usr/lib64/libpython2.7.so.1.0
#20 0x00007ffff74d4bad in __libc_start_main () from /lib64/libc.so.6
#21 0x00000000004008c9 in _start ()

I have python 2.7.1 and amd64 linux distributive (gentoo). I did not
see this problem on x86 linux.
Thanks.

On 8/4/2011 8:26 AM, Xavier Gnata wrote:
> I think the main question is : How do you produce a arbitrary long
> list of colors to use it as a color gradient (as input to
> set_color_cycle )?


See this thread
http://www.mail-archive.com/mat...@li.../msg21569.html
for an approach to the underlying question, which I take to be,
how to parametrize line color for a collection of lines.

Cheers,
Alan Isaac

hi,

I want to overplot N curves calling the plot(X) function N times.
I also would like to have a way to which curve has been drawn first and so on.

If N would en small and constant, I could simply call color_cycle with
a short list as parameter...but it is not quite an option with up to
50 curves...

How could I setup a color_cycle which look like a color gradient
(let's say "the first curve in red, the last one in green and the
other in between).

I think the main question is : How do you produce a arbitrary long
list of colors to use it as a color gradient (as input to
set_color_cycle )?

xavier