import matplotlib.pyplot gives ImportError: No module named _tkagg

[jhn]

The default TkAgg backend for matplotlib dosn't work and gives the folowing error when
pyplot is imported in both python 2.6 and 2.5

>>> import matplotlib.pyplot
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.6/dist-packages/matplotlib/pyplot.py", line 75, in <module>
    new_figure_manager, draw_if_interactive, show = pylab_setup()
  File "/usr/lib/python2.6/dist-packages/matplotlib/backends/__init__.py", line 25, in pylab_setup
    globals(),locals(),[backend_name])
  File "/usr/lib/python2.6/dist-packages/matplotlib/backends/backend_tkagg.py", line 8, in <module>
    import tkagg # Paint image to Tk photo blitter extension
  File "/usr/lib/python2.6/dist-packages/matplotlib/backends/tkagg.py", line 1, in <module>
    import _tkagg
ImportError: No module named _tkagg

However if you change the backend in /etc/matplotlibrc to QT4 (and maybe others) everything works fine

using matplotlib 0.98.5.2-1ubuntu1 on kubuntu 9.04 alpha 5

[Václav Šmilauer (eudoxos)]

Confirming. This is a regression from intrepid and cen be verified by inspection of package contents list. _tkagg.so doesn't exist anymore in jaunty.

[Václav Šmilauer (eudoxos)]

BTW no mention of such change in changelogs, either.

[Václav Šmilauer (eudoxos)]

After rebuilding the package locally, _tkagg.so installs just fine. OTOH then I get RuntimeError: Could not find the matplotlib data files from /usr/lib/python2.6/dist-packages/matplotlib/__init__.py:479. But that one can be worked around by setting MATPLOTLIBDATA=/usr/share/matplotlib env. var.

[Václav Šmilauer (eudoxos)]

Correcting my mistake in the last post: should read MATPLOTLIBDATA=/usr/share/matplotlib/mpl-data .

[Daniel J Blueman (danielblueman)]

I find that rebuilding matplotlib addresses the issue, without need for setting the environment variable here.

[Andrew Straw (astraw)]

I can confirm this bug with 0.98.5.2-1ubuntu1. I have a patch to the source and confirmed that it builds the _tkagg module and fixes this bug. I include the debdiff file produced from the source I used.

[LaserJock (laserjock)]

Andrew, thanks a ton for the debdiff. One question though, what are the changes in debian/rules for? Why are you rm'ing the build directory?

[Andrew Straw (astraw)]

Jordan, the "rm -rf build" is in the clean target -- this is only used for cleaning up the tree after a build and before a new one. "dh-clean build", which I removed, was breaking if the build directory wasn't there, whereas the rm command does not break. Really, I should probably test for the existence of the directory and only delete it in that case, but I couldn't remember the syntax, whereas "rm -rf" is pretty much hardwired into my spinal ganglia.

[Benjamin Drung (bdrung)]

0.98.5.2-1ubuntu1+0ads1 should be changed to 0.98.5.2-1ubuntu2.

[Benjamin Drung (bdrung)]

I have added the bug number to the changelog entry. I can confirm that this patch works. So please sponsor Andrews patch.

[Daniel Holbach (dholbach)]

Uploaded. Sitting in the queue.

[Launchpad Janitor (janitor)]

This bug was fixed in the package matplotlib - 0.98.5.2-1ubuntu2

---------------
matplotlib (0.98.5.2-1ubuntu2) jaunty; urgency=low

  * Really build with tcl/tk8.5 as python-tk was build with tcl/tk8.5
    (LP: #337469).

 -- Andrew Straw <email address hidden> Sat, 21 Mar 2009 14:55:09 -0700

[Youen (youen-peron)]

I have the same bug with an upgraded Nasty from a clean Manvrik. I don't known if i must open a new issue or reopen this one.

[Jan Groenewald (jan-aims)]

This bug is present on Natty Development branch at the moment.
Should a new bug be filed?

jan@milaine-laptop:~$ python -c "import pylab"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/pymodules/python2.7/pylab.py", line 1, in <module>
    from matplotlib.pylab import *
  File "/usr/lib/pymodules/python2.7/matplotlib/pylab.py", line 247, in <module>
    from matplotlib.pyplot import *
  File "/usr/lib/pymodules/python2.7/matplotlib/pyplot.py", line 78, in <module>
    new_figure_manager, draw_if_interactive, show = pylab_setup()
  File "/usr/lib/pymodules/python2.7/matplotlib/backends/__init__.py", line 25, in pylab_setup
    globals(),locals(),[backend_name])
  File "/usr/lib/pymodules/python2.7/matplotlib/backends/backend_tkagg.py", line 8, in <module>
    import tkagg # Paint image to Tk photo blitter extension
  File "/usr/lib/pymodules/python2.7/matplotlib/backends/tkagg.py", line 1, in <module>
    import _tkagg
ImportError: No module named _tkagg
jan@milaine-laptop:~$ dpkg -l |grep python-tk
ii python-tk 2.7-2ubuntu2 Tkinter - Writing Tk applications with Python
jan@milaine-laptop:~$

[the_vorpal_blade (the-vorpal-blade)]

I can confirm that this is an issue in Natty. It happened with today's batch of updates, since it was not a problem yesterday.

[Marcel Stimberg (marcelstimberg)]

Please follow bug #752647 for this issue in Natty.