No subject

[Helena Mitasova]

Augus asks:

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I'm trying to use s.surf.tps. My sites file has been generated via
s.in.ascii and looks like:
1000|1000|123
1050|1020|200
etc
I get a warning per line saying that my categories are not preceded by
a # sign, and
then the result is 0 raster file.
 
Does s.surf.tps need any kind of special sites file input?
(Post the answer to the list if you think my problem could be a general
one)
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Although this is a standard GRASS feature,
I have got this question already couple of times and  I have found that there
is not a proper reference or explanation of this in GRASS users and/or
GRASS programmers manual so here is the answer :

yes, your data must look like:

1000|1000|#123

this is because the category is a numerical value and you have to
let GRASS know it by putting # there. Without the # sign, it 
interprets the site label as character string. 
Thank you for your question, we will make sure that the proper 
description of sites format gets into manuals (and I will check
whether it would be possible to include it as an option to s.in.ascii,
as I am missing it there too)

Comments for Chris, Simon and others on interpolation issues follow
soon. Sorry, for giving the incorrect reference to Geoderma paper,
I had only the manuscript from Mike Hutchinson and I was told that it
will probably come out in 1992.

I hope this will help, good luck,

Helena Mitasova
helena at zorro.cecer.army.mil