[GRASS-user] ...|no data problem

[Martin Wegmann]

On Wednesday 02 May 2007 15:58, Glynn Clements wrote:
> Martin Wegmann wrote:
> > I think it is a very simple problem but I don't get it.
> >
> > I have a raster which I want to convert to integer but doing so results
> > in areas with null() values.
> > When I look at the input raster (r.what) I get areas which look like
> > this:
> >
> > -1.59582443346|6.02450629749||927119811.912364006|
> >
> > which also look fine in the integer conversion, but other areas give
> > following r.what infos:
> >
> > -2.14304204004|6.63535385832||2633784216.1745109558|no data
> >
> > these areas results in null() values after integer conversion.
>
> Note that 2633784216 is too large to be represented as an integer; the
> range of integers is -2147483647 to +2147483647 inclusive.
>
> If you have values outside that range, you will need to rescale.

oh, yeah, thanks - I did:

MIN=`r.info -r "$GIS_OPT_input" | grep min | cut -f2 -d=`
 
MAX=`r.info -r "$GIS_OPT_input" | grep max | cut -f2 -d=`
 
r.mapcalc "tttemp1 = ( ( $GIS_OPT_input - abs($MIN) ) / (abs($MAX) - 
abs($MIN)) ) * ( $GIS_OPT_range_max - $GIS_OPT_range_min) + 
$GIS_OPT_range_min"

know it works, thanks!

Martin