Re: [Matplotlib-users] dynamic update in TkAgg ? (more)

[John H. <jdh...@ac...>]

>>>>> "Gary" == Gary Pajer <pa...@in...> writes:

    Gary> I took out a wristwatch and timed it instead of guessing.  I
    Gary> get three frames per second.  It's about 4x from where we
    Gary> started, but still slow.  I guess I'm just underpowered,
    Gary> although a couple of years ago this was a powerhouse.  It
    Gary> seems that matplotlib may not be suited to this task.  I
    Gary> don't think it should take 2 GHz just to power a stripchart.

I agree.  The current design of matplotlib doesn't really support this
kind of use because it redraws the entire figure every time and does
too much duplicate work at the python level.  It shouldn't be too hard
to add some specialized functions for agg that support strip charts.
I've been planning to do it because we have a need for it here, and
there is some general on c.l.python for this kind of plotting feature
in python.

So I can start mulling over the design, can you tell me what kinds of
real time updates you need - only solid lines or arbitrary symbols
like 'o' too?  Anything else besides line plots?

I'm envisioning some extension code that talks directly to the data
source and to the agg backend, updating only part of the canvas.  The
blitting functions for GTK/WX/Tk Agg would have to be extended to blit
only a region of the canvas.

JDH