[GRASS-user] interpolating data points

[Paul Pick]

Hi all,

 I have a bunch of data points on a 2 degree lat/lon grid.
I want to interpolate that and extract data on a 0.5 degree
lat/lon grid.

 What I've done is:

1. v.in.ascii to load a vector map of points at 2 degree interval

2. create a temp file holding '$lat $lon 0.0' lines for each
   0.5 degree point I want to extract

3. v.in.ascii to load temp file of 0.5 degree grid 

4. g.region to 2 degree data extents with res="00:20"

5. v.surf.idw to create raster from 2 degree grid

6. v.what.rast to fill 0.5 degree grid from raster

7. v.to.db and v.db.select to dump 0.5 degree grid to stdout

 This, as you can imagine, is slow to execute. Am I missing 
a much faster way to do this?

-- 
Paul Pick <paul.pick at ec.gc.ca>
Informatics Services Unit Gagetown
Chief Information Officer Branch, Environment Canada
[CSN] 432 2082 [CIV] 506 422 2000 x 2082 [FAX] 506 422 1443