Matplotlib window freezes using intreractive plot in qtconsole

[napopa]

Hi,

I'm using ipython stable release, python 2.7.3 and matplotlib 1.1.0, everything installed with homebrew and pip on Mac OS 10.7.4

If I start Ipython with the qtconsole and activate the ion() interactive mode, plotting something would cause the matplotlib window to pup up and freeze without actually displaying anything more that the grey background. This happens with both the PySide and MacOSX backends. To close the plot window I have to close ipython.
If i try the same steps in a shell-based ipython prompt everything works.

[fperez]

Are you starting the matplotlib support by providing the --pylab startup flag or calling the %pylab magic?

[napopa]

I was manually importing pylab with

from pylab import *

as I do in any standard python console. This works in a shell-based ipython but not in qtconsole.
Providing the pylab switch or the magic %pylab both make the interactive plotting work in the qtconsole as well.

Is this an expected behaviour ?

[fperez]

Yes. The fact that not using pylab works is an accident that's OS and backend dependent and can't be relied upon. The only officially supported way of using matplotlib interactively with possibly multiple plots and a fully non-blocking window is to use --pylab or %pylab.

Closing as not a bug.

[napopa]

I see, thanks for clarifying!

[Alexis-benoist]

Hello,

I'm having the same issue. What do you mean by the --pylabflag, does what I did below seems reasonable?

Thank you in advance!