Ensure %gui qt works with new Mayavi and pylab

[Fernando Perez]

Right now mayavi/qt is only on SVN, but eventually we need to ensure that %gui qt allows mayavi/qt and pylab/qt to work together.

For more details:
http://mail.scipy.org/pipermail/ipython-dev/2010-January/005728.html

[Michele Mattioni (mattions)]

Expected:

- The window should respond to the command (zoom, rotate...)
   and not freeze.

- The prompt should be back and be responsive.

[Michele Mattioni (mattions)]

Ok, this is weird.

Sometimes the window freeze, sometimes respond to the command (like zoom and rotate).

However I can't get the prompt back and ready to insert a new command.

[Brian Granger (ellisonbg)]

Mayavi and pylab are probably doing some funny things with the event
loop that is messing up
things. It will probably require someone looking through the
Mayavi/pylab/traits code carefully
to look for these things.

Cheers,

Brian

On Mon, Jan 18, 2010 at 4:02 AM, Michele Mattioni <email address hidden> wrote:
> Ok, this is weird.
>
> Sometimes the window freeze, sometimes respond to the command (like zoom
> and rotate).
>
> However I can't get the prompt back and ready to insert a new command.
>
> --
> Ensure %gui qt works with new Mayavi and pylab
> https://bugs.launchpad.net/bugs/508953
> You received this bug notification because you are a member of IPython
> Developers, which is subscribed to IPython.
>
> Status in IPython - Enhanced Interactive Python: Confirmed
>
> Bug description:
> Right now mayavi/qt is only on SVN, but eventually we need to ensure that %gui qt allows mayavi/qt and pylab/qt to work together.
>
> For more details:
> http://mail.scipy.org/pipermail/ipython-dev/2010-January/005728.html
>
>
>

--
Brian E. Granger, Ph.D.
Assistant Professor of Physics
Cal Poly State University, San Luis Obispo
<email address hidden>
<email address hidden>

[Fernando Perez (fdo.perez)]

The attached script can be run in ipython trunk-dev, and shows the problem:

maqroll[Desktop]> ip
Python 2.6.4 (r264:75706, Dec 7 2009, 18:45:15)
Type "copyright", "credits" or "license" for more information.

IPython 0.11.bzr.r1346 -- An enhanced Interactive Python.
? -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help -> Python's own help system.
object? -> Details about 'object'. ?object also works, ?? prints more.

In [1]: gui -a qt
Out[1]: <PyQt4.QtGui.QApplication object at 0x93086ac>

In [2]: run qt_embedding.py

Button pushed

### Terminal is frozen here, until we close the mayavi window.

In contrast, if we run the same script in 0.10 with -q4thread:

(ipython-0.10)maqroll[Desktop]> ip -q4thread
Python 2.6.2 (release26-maint, Apr 19 2009, 01:56:41)
Type "copyright", "credits" or "license" for more information.

IPython 0.10 -- An enhanced Interactive Python.
? -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help -> Python's own help system.
object? -> Details about 'object'. ?object also works, ?? prints more.

In [1]: run qt_embedding.py

In [2]: 1+1 # terminal accepts input though window remains open
Out[2]: 2

In [3]: Button pushed

Thanks to Gael for the feedback to fix the api calls in the example script.