[Pkg-exppsy-maintainers] Was: ridge... now VALGRIND time

Per B. Sederberg persed at princeton.edu
Tue Jan 15 23:23:38 UTC 2008


On Jan 15, 2008 6:18 PM, Yaroslav Halchenko <debian at onerussian.com> wrote:
>
> > Typically we collect continuous data for about 1 hour at around 500Hz.
> >  That gives us 1.8 million samples per channel with up to around 128
> > channels.  Definitely doable.
> if my calculations correct it would be
> *octave:2> (1.8*10^6*128*8)/1024^3
> ans = 1.7166
> 1.7GB of data... not too bad... should be managable to work on in memory
> ;-)
>

Indeed, but as soon as you calculate phase and power for all of those
samples, it becomes much much bigger.

> > However, I think one very viable option is to store EEG in the NetCDF
> > data format, which has some good python wrappers that allow you to
> > access the dataset as a numpy array, but not load the entire thing
> > into memory.  There are even wrappers for matlab (if people would like
> > to do such a thing.)
> That sounds great! Someone should write NetCDFDataset! We should add
> that to TODO ;-) Shouldn't be too difficult I think...
>
> > The only problem is that the latest NetCDF is not at a stable release
> > the last time I checked.  Still possibly usable, but a moving target.
>
> Is API changing wildly?
>

On closer look, the person writing the best wrapper recently released
a version that also supports the stable version of NetCDF and does it
far better than the current Scientific python version:

http://netcdf4-python.googlecode.com/svn/trunk/docs/netCDF3-module.html

It's only dependencies are already in debian testing, so it shouldn't
be crazy to make a debian package for it.  I'm still a novice with
this packaging business, but I could give it a whirl.  It does
certainly fall under the realm of what pkg-exppsy is trying to do :)

Best,
Per


> --
>
> Yaroslav Halchenko
> Research Assistant, Psychology Department, Rutgers-Newark
> Student  Ph.D. @ CS Dept. NJIT
> Office: (973) 353-5440x263 | FWD: 82823 | Fax: (973) 353-1171
>         101 Warren Str, Smith Hall, Rm 4-105, Newark NJ 07102
> WWW:     http://www.linkedin.com/in/yarik
>
> _______________________________________________
> Pkg-exppsy-maintainers mailing list
> Pkg-exppsy-maintainers at lists.alioth.debian.org
> http://lists.alioth.debian.org/mailman/listinfo/pkg-exppsy-maintainers
>



More information about the Pkg-exppsy-maintainers mailing list