Digitized contour lines

Hello!

I am trying to generate an elevation model from a set of digitized
contour lines. The problem is that the contourlines does not extend
to the edges of the current region, and therefore the r.surf.contour
program does not work properly. Does anyone know

1)
if there exists programs that can artificially extend contourlines to
the edge of current region.

or

2)
if there exists a r.surf.contour program that can use masks, so that the
contourlines dont have to be extended.

Any other comments on how I can solve this problem would be highly
appreciated.

Trond Rinde
--

Siv.ing. Trond Rinde

Institut f. Wasserwirtschaft, Hydrologie und konstruktiven Wasserbau
Universitet f. Bodenkultur
A-1190 Wien, Nussdorfer Laende 11

tel: 1 36 92 924 352
fax: 1 36 92 924 350
email: trinde@donau.boku.ac.at

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