[SciPy-user] [Newbie] High-performance plotting of large datasets

[Bryan Cole]

Hi,

I'm an ex-LabView user, now using python for lab data-acquisition and
analysis for some years now. It's well worth the switch.

Your best bet is
http://pyqwt.sourceforge.net/


You're right, matplotlib/chaco are too slow for "interactive real-time"
type work. The strengths of these packages are their
presentation-quality output (vector and anti-aliased bitmap graphics).

For data-acquisition applications, I prefer wxPython  to Qt (I may move
to something based on Traits/ETS once I figure out how to install it).
For GUIs I have a home-made plotting widget which is fast enough for
real-time work. Unfortunately, I'm not yet in a position to post it
publicly. If you need *really* high performance, it's not too hard to
write a plot-widget using PyOpenGL directly.

Bryan


On Thu, 2008-02-28 at 09:57 +0100, scipy-user at onnodb.com wrote:
> Hi all,
> 
> Using LabVIEW software for our data analysis at the moment, I'm
> currently looking for alternatives. Especially since LabVIEW's
> "graphical" programming language is somewhat cumbersome for some of
> the things we're doing --- an iterative language would often be much
> easier. (Actually, I personally don't like the graphical way of
> programming at all :) )
> 
> Python seems to be a great alternative, although I haven't been able
> yet to get things up & running the way I'd like. The main 'problem' is
> that LabVIEW contains a lot of high-performance library code for
> plotting data. I've been experimenting with SciPy and matplotlib, but
> those libraries are just *way* slower than LabVIEW when plotting large
> data sets (in our case, it's a current trace with a few MBs of data).
> I'd like to plot a current trace, so that the user can quickly zoom in
> & out, and pan using a horizontal scroll bar, but how should I do
> this? (I've looked around for examples a bit, but being a newbie, it
> can be hard to find your way around such a huge community).
> 
> Another issue appears to be the creation of simple user interfaces.
> This is very intuitive in LabVIEW, but could someone here give some
> advice on a way to combine a UI and plot windows in a not-so-difficult
> to learn way in Python? What's your own experience?
> 
> I've spent some time on looking at various packages and frameworks
> like Traits, Chaco and Envisage, but I just can't seem to wrap my head
> around them.
> 
> I'm looking forward to any help; thank you very much in advance!
> 
> Best regards,
> 
>