[GRASSLIST:7069] Re: Introduction and "Cookbook" question

[Hamish]

> Here is my question. I came across a useful "recipe" for converting
> downloaded Landsat data from the GLCF with GRASS from 
> http://www.oryx.com/ams/landsat.html and was impressed at how quick
> one could develop a simple fused Brovey image thanks to this wonderful
> "recipe". Now I have a question: has anyone developed a "ccokbook" of
> commands like this, specifically for
>  
> SRTM data to contours, aspect and slope.
> Importing and using VMAP data in GRASS,
> Importing DCW into GRASS,

all detailed in the upcoming GRASS-News vol 3.


but quickly:

SRTM:
 (Use the development version in CVS if you want US 1-arcsec support)

r.in.srtm
g.region rast=imported_srtm
r.fillnulls
r.slope.aspect
r.contour

All these modules are very straight forward and painless.


VMap0, DCW:
same thing, no? It's been 10+ years since I've used DCW much so I can't
recall if the structure is exactly the same, but Vmap0 should be
"version 2" of DCW and is freely available, so no need for DCW, right?

Import here is a little harder- you need to build GDAL with OGDI support
and do some cleaning of the file structure. Detailed in Markus's article
in the upcoming edition of GRASS-News.


Digital coastline extractions from NOAA's coastline extractor are very
nice:
  http://www.ngdc.noaa.gov/mgg/shorelines/shorelines.html

(Mapgen/Matlab vector line importer in 6.1-cvs; Arc-UnGen is in 
GRASS 5.4 as v.in.arc, covered by v.in.ogr in GRASS 6?)


> General topographical analysis e.g, Viewshed analysis and profiles.

r.terraflow   : watershed analysis for massive DEMs
r.los, r.cva  : viewshed analysis (r.los is stale; Google for r.cva)
r.profile, r.transect, d.profile:  profile analysis

Viewshed analysis is still a weak area. With luck one day the existing
GRASS 6 port of r.cva can become part of GRASS.


> I hope this is not a FAQ. Sorry if it is!

be sure to check out the GRASS wiki site. Collaborative FAQ.
  http://grass.gdf-hannover.de/twiki/bin/view




Hamish