[winGRASS] How to convert a dxf file of contour lines to DEM with grass?

[Markus Neteler]

On Wed, Mar 13, 2002 at 03:28:32PM +0800, shawn SHIH wrote:
> I have a dxf file of contour lines, and I want to generate a DEM with these contour lines.  As I know, there are 4 step to be done.
> (1) convert the dxf file to dig formate with v.in.dxf.
> (2) edit category with v.support. The question is "How to set the category relate to the right contour line", (the contour lines value are from 100 to 750 period 50).
> (3) convert vector file to raster file with v.to.rast.
> (4) interpolate raster file to DEM with r.surf.contour. 
> 
> Am I right? Is there anything must pay attention to? Is there any better way to accomplish that job.
> 
> Thanx
> 
> shawn SHIH

Hi,

briefly you do:

v.in.dxf dxf=contour.dxf line=CURVES
v.in.dxf3d dxf=contour.dxf line=CURVES
v.support contour.CURVES
d.vect contour.CURVES   
d.what.vect 

CURVES is a layer name, adjust as appropriate. If you do not specify it,
all layers should be imported. For v.in.dxf3d it might be necessary to
give the layer name which contains the contours.

Then you can proceed with
g.region res=xxx
v.to.rast
r.surf.contour

or with v.surf.rst (so no v.to.rast needed).

Hope this helps,

 Markus Neteler