[GRASSLIST:5889] Question about s.to.rast

Victor Wren vwren at timension.com
Thu Mar 27 16:55:47 EST 2003


I'm trying to bring in a large number of elevation files, in preparation for 
turning them into a surface map.  The file is about 150,000 floating-point 
locations in this format:
2887690.49718   1673263.622019  10969.170819 @" "
2887694.185556  1673257.944703  10969.240661 @" "
2887640.301113  1673223.419907  10972.161139 @" "
.......

I'm importing them to a sites file with:
s.in.ascii input={infilename} sites={sitesname} d=3

This goes well, and when I do d.sites, they show up where they're supposed to 
be.

I then want to convert them to a raster map.  This is the command I use:

s.to.rast input={sitesname} output={rastname} field=dim findex=3

(I've tried without field and findex, and it doesn't like it  I'm not quite 
sure exactly what I'm doing, but it seems to work.)  It says: 

Using size option 0
Sites map Type: 0, Dims: 3, Strs: 1, Dbls: 0

It warns me about dropping multiple sites on one cell (which is fine -- the 
sites are overly dense, and the elevations should be very close), and 
crunches along for awhile, then segfaults.

I thought it might have a problem with the number of sites, so I trimmed it 
back to about 48,000 and it still segfaulted.  I trimmed it again 1,000, and 
it successfully finished.  I only have to do this 600 more times, and I'll be 
done with the first step.

What's the practical limit to the number of sites that s.to.rast can cope 
with?

Victor Wren





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