[GRASS-user] profile and tangential curvature negative XY coordinates

GRASS GRASS user
1

Hello all,

I am a new GRASS 6.4 user (1 month). I want to calculate topograhic parameters (profile and tangential curvatures) from a 1-m DEM that has negative XY coordinates (EPSG2446) north -210,000 south -213,000 west -60,500 east -55,500. Resulting rasters have extremely large values.

Is it because of spatial reference? is there a workaournd?

I appreciate any comment. Thank you,

Edgar Pimiento Chamorro
e_pimiento@yahoo.com

2

Hello all,

Welcome:

I am a new GRASS 6.4 user (1 month). I want to calculate topograhic parameters (profile and tangential curvatures) from a 1-m DEM that has negative XY coordinates (EPSG2446) north -210,000 south -213,000 west -60,500 east -55,500. Resulting rasters have extremely large values.

SO your region is 3 km X 5 km, or 3000 m X 5000 m (I’ll assume you have the region resolution set to 1 m?? Check this with g.region -p)
In this case you’ll be working with a raster of 15,000,000 cells. It’s a large region by not unreasonable size. With any recent computer you should be able to do profiles and curvature.
What are the values that you say are “extremely large”??

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Micha Silver
Arava Development Co. +972-52-3665918
[http://surfaces.co.il](http://surfaces.co.il)