Re: Re: [GRASS-user] Testing i.pca ~ prcomp(), m.eigensystem ~ princomp()

3 messages Options
Embed this post
Permalink
hamish-2

Re: Re: [GRASS-user] Testing i.pca ~ prcomp(), m.eigensystem ~ princomp()

Reply Threaded More More options
Print post
Permalink

Nikos:
> > http://grass.osgeo.org/wiki/Principal_Component_Analysis

Roger:
> Good, thanks. There you say that you are using "some MODIS
> surface reflectance products". I guess it will be easier to
> check things if the data (GRASS location) are available, so
> that others can try the same calculations. Would it be possible
> to make one or more test sets available, and link them from thw
> Wiki?

better yet, use the standard Spearfish SPOT imagery sample dataset
for the examples. (as m.eigensystem and now i.pca help page
examples do, probably others)

is there a way to change text color in MediaWiki? it might be
easier to highlight m.eigensystem output rows by color instead
of '#'s.


idea for possible google summer of code 2009 project: overhaul i.*
modules/lib for grass7. US$4.5k bounty :)


cheers,
Hamish



     

_______________________________________________
grass-stats mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-stats
Nikos Alexandris

Re: Re: [GRASS-user] Testing i.pca ~ prcomp(), m.eigensystem ~ princomp()

Reply Threaded More More options
Print post
Permalink

> Roger:
> > Good, thanks. There you say that you are using "some MODIS
> > surface reflectance products". I guess it will be easier to
> > check things if the data (GRASS location) are available, so
> > that others can try the same calculations. Would it be possible
> > to make one or more test sets available, and link them from thw
> > Wiki?

Hamish:
> better yet, use the standard Spearfish SPOT imagery sample dataset
> for the examples. (as m.eigensystem and now i.pca help page
> examples do, probably others)

I will eventually try to re-perform all test with spearfish as well.
Except if someone else, interested in PCA, is willing to do it :-p.

Sorry that I haven't done that before. I preferred to play around with
data from my projects.

Kind regards, Nikos

_______________________________________________
grass-stats mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-stats
Markus Neteler

Re: Re: [GRASS-user] Testing i.pca ~ prcomp(), m.eigensystem ~ princomp()

Reply Threaded More More options
Print post
Permalink
In reply to this post by hamish-2
On Thu, Mar 12, 2009 at 8:26 AM, Hamish <[hidden email]> wrote:
>
> Nikos:
>> > http://grass.osgeo.org/wiki/Principal_Component_Analysis
>
...
> better yet, use the standard Spearfish SPOT imagery sample dataset
> for the examples. (as m.eigensystem and now i.pca help page
> examples do, probably others)

Let me suggest the Landsat imagery in the North Carolina location
which are more recent (the Spearfish *imagery* sample dataset
isn't that great).

Markus
_______________________________________________
grass-stats mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-stats