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<TITLE>Re: [GRASSLIST:8202] Making a raster coordinate a value</TITLE>
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<FONT FACE="Verdana, Helvetica, Arial"><SPAN DEFANGED_STYLE='font-size:12.0px'>IR17;d like to know the answer to this question also. How do you reclassify (or simply assign a value to) a raster cell with a particular set of xy coordinates rather than a particular cell value. I also need to know this for implementing agent modeling results in GRASS.<BR>
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Thanks<BR>
Michael<BR>
__________________________________________<BR>
Michael Barton, Professor of Anthropology<BR>
School of Human Evolution and Social Change<BR>
Arizona State University<BR>
Tempe, AZ 85287-2402<BR>
<BR>
phone: 480-965-6213<BR>
fax: 480-965-7671<BR>
www: <a href="http://www.public.asu.edu/~cmbarton">http://www.public.asu.edu/~cmbarton</a> <BR>
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<HR ALIGN=CENTER SIZE="3" WIDTH="95%"><B>From: </B>Joel Peter William Pitt <joel.pitt@gmail.com><BR>
<B>Date: </B>Wed, 7 Sep 2005 16:36:25 -1200<BR>
<B>To: </B><grasslist@baylor.edu><BR>
<B>Subject: </B>[GRASSLIST:8202] Making a raster coordinate a value<BR>
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Hi all,<BR>
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What is the simplest way to get get a singular cell in a raster map to be set to a value,<BR>
irregardless of the current regions resolution?<BR>
<BR>
More specifically I want to set closest cell to the origin (0,0) to have value 1. But only 1 cell must be present, and it must work for any resolution - although I'm currently concerned with working at res=1.<BR>
<BR>
I've been playing with mapcalc but the way it calculates x() and y() seems odd and round() rounds them to either 1 or -1, skipping 0. int() truncates leaving two rows/columns with a value 0.<BR>
<BR>
I'm aware this is a bizarre use of GIS, I'm developing a modelling framework and I'm currently looking at behaviour from the origin in order to analyse it's general behaviour before applying it to a real landscape.<BR>
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Thanks for any help,<BR>
<BR>
Joel<BR>
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