Vector lines to areas

[Randy Hills]

> 
> 
>         I have a vector file of lines only, These lines form a set of basins.
>I need to make a mask such that there is only one or as many as the user wishes
> basins visible. The problem is that since there are only lines, how to get
> areas out of them and then I was thinking that I could make a mask by running
> v.to.rast. Any suggestions ??????
> 
> Nalneesh Gaur
> 

I am not sure how far you need to carry this concept, but we had a similar
need to develop masks from a vector file which contained a group of basins.
After cleaning up the vector file and labelling areas in v.digit, we wrote
a program called create_outline which would extract individual basins or
groups of basins from this map and output a vector containing an outline
of the composite of these basins.  Running v.to.rast would then create the
needed mask.  This program can be made available, however, we currently 
haven't developed any documentation for it.

Randy Hills