Data Crunching and Charting....

[tbonejo]

Hi all.

Question: I have a project nearly complete written in VB.Net using
charts from 3rd party vendors...expensive, yes, fast, not really. The
data I am plotting is about 30 columns by 3000-9000 rows, all in a tab
delimited file(43 files total). My question is whether or not I can
accomplish the same in Python utilizing Matplotlib or Chaco for
plotting, at a much faster speed. In my app it takes a while to loop
through all the rows/columns to plot the data. Im just curious whether
there may be a big boost in performance using python. Also I use
spreadsheet style grids for displaying data. I was looking at the grid
control for wxpython and that seems a nice fit. Anyone with experience
with it have any opinions, Id appreciate them. Alot of the programming
I do deals with crunching data and charting it. Sometimes I wonder
whether python would be a much better canidate for this type of work
rather than what Im using now.


Thanks.


Tom

 

[Mr BigSmoke]

Hi Tom.

I had more or less the same problem about 1 year and a half ago...
Since then i've tried either Matplotlib and chaco. I've started using
matplotlib but for some features reason i've decided to use only chaco.
Chaco is really cool but has some neg. points:
- documentation is not really detailed and there are really few
examples
- not supported anymore (at least i've never found any place supporting
it.. if anyone know bout any support tell me!!)
- sometimes it's really hard to look into it's code to extend some
classes...

The data i have to plot goes from very few curves and ticks to about
10/12 curves, 15000 ticks and range from -1 to 100000+ in Y axis.

Th plotting speed is good... but more data u plot, more problem u get!!
Like, zooming feature is not very "solid", and get's worse with tons of
data..., some features are missing (or at least i've never found them!!
I'd be very happy if someone says that i'm wrong and shoe me them!!),
like showing the values of th curvers when i pass the mouse on it, of
the highlighting a point in the curve if i clck on it!!

Fabio Pliger

 

[tbonejo]

Thanks for the response. I did look at the plot class for wxpython and
that looks worth checking out too. I really just need to plot the data,
optionally print, and save each as an image. Sounds like from what
you've done it is alot faster than what Im doing now.

Thanks again.

 

[Robert Kern]

Hi Tom.

I had more or less the same problem about 1 year and a half ago...
Since then i've tried either Matplotlib and chaco. I've started using
matplotlib but for some features reason i've decided to use only chaco.
Chaco is really cool but has some neg. points:
- documentation is not really detailed and there are really few
examples
- not supported anymore (at least i've never found any place supporting
it.. if anyone know bout any support tell me!!)

http://code.enthought.com/chaco/

You're probably using an extremely old version.

--
Robert Kern
(e-mail address removed)

"In the fields of hell where the grass grows high
Are the graves of dreams allowed to die."
-- Richard Harter

 

[Mr BigSmoke]

Great!! I kept looking enthought site everyday for 2/3 months about one
year ago... but it always had old chaco versions, no news... Then i
posted questions about it here at comp.lang.python and some people said
the project had been abbandoned... Great to know that it's not true!!
TNX VERY MUCH!!

Fabio Pliger