rqt_plot issues on osx el-capitan

[mikepurvis]

rqt_plot issues on osx el-capitan

[robert-preissl]

I found the issue and posting here in case folks have similar troubles.
It seems that in the latest matplotlib things have changed around the "NavigationToolbar". as a result MatPlotLib could not be loaded. to fix I changed the code in "mat_data_plot.py" from "NavigationToolbar2QTAgg" to "NavigationToolbar2QT". and it works fine now.

[mikepurvis]

Looks like the code should have accounted for that:

https://github.com/ros-visualization/rqt_common_plugins/blob/master/rqt_plot/src/rqt_plot/data_plot/mat_data_plot.py#L82-L85

Can you describe more about the issue you encountered, in case someone else hits it?

[mikepurvis]

That change went in here: https://github.com/ros-visualization/rqt_common_plugins/blob/master/rqt_plot/src/rqt_plot/data_plot/mat_data_plot.py#L82-L85

@dirk-thomas Perhaps the check should be reversed, so we try the new name first? I'm suspecting that we're pulling in a compatibility API or something.

[dirk-thomas]

The current code already catches the import error and should have fallen back to the suggested import. Therefore I don't see any reason to change the current code.

@robert-preissl If you could provide more information about which version of matplotlib you are using as well as the exact code of rqt_plot that might help identifying why it failed for you.

[mikepurvis]

My argument is that NavigationToolbar2QTAgg and NavigationToolbar2QT are not exactly aliased to each other— one is a subclass. So it might be better behaviour to just import NavigationToolbar2QT without the fallback. See the changelog for 1.5.x: http://matplotlib.org/api/api_changes.html#remove-navigationtoolbar2qtagg

@robert-preissl Which version of matplotlib have you got on your system? Can you give us the first few lines of pip show matplotlib for you? I'm on 1.5.1 here.