If you want to test for the specific cell in which the given
coordinates lie, you may be better off converting the coordinates to a
row/col based upon the region settings, then testing against the
results of row() and col() (but note: row() and col() are 1-based, not
0-based).
Testing
G. Allegri wrote:
If you want to test for the specific cell in which the given
coordinates lie, you may be better off converting the coordinates to a
row/col based upon the region settings, then testing against the
results of row() and col() (but note: row() and col() are 1-based, not
Yer, but as mapcalc has some built-in functions like x() and y() to
retrieve the x-y coordinates, I think it could be easy to trasform
them in projected coordinates.
I'm writing a few lines in C to solve it, but I think I'll take a look
to r.mapcalc code to see if it would be possible to add
G. Allegri wrote:
How can I control mapalgebra if statements on the base of the
coordinates values of a cell?
The base problem is to change the values of some specific cells on the
base of their coordinates.
r.mapcalc $outmap = if(abs(x() - $x) $eps abs(y() - $y)
$eps,$newval,$inmap)
On 14/07/08 12:17, G. Allegri wrote:
Yer, but as mapcalc has some built-in functions like x() and y() to
retrieve the x-y coordinates, I think it could be easy to trasform
them in projected coordinates.
I'm writing a few lines in C to solve it, but I think I'll take a look
to r.mapcalc code to
Thanks Glynn. Exaustive explanation :-)
So I just need to check if the difference abs($x-x()) is lower then
half the resolution...
2008/7/14 Glynn Clements [EMAIL PROTECTED]:
Moritz Lennert wrote:
Well, this works:
r.mapcalc brol3=if(y()=9521600 x()=427000,1,null())
but this doesn't:
Moritz Lennert wrote:
Also note that the calculation involves multiplying by the resolution.
You mean internally by mapcalc, or that I should include resolution into
the calculation ?
Internally.
The point is that if you have e.g. a 100m x 100m square, and you set
rows = cols = 300, so
