The trick for many things in GRASS is to "think raster" instead of thinking vector.
Make a raster DEM from your map (if you don't already have one). Query the raster (e.g., with r.mapcalc or r.reclass) to create a raster of elevations between your contour lines (e.g., in r.reclass the specification 1000 thru 1500 = 1). Run r.to.vect on the queried map to turn it into an area. Michael On Feb 25, 2012, at 10:00 AM, <[email protected]> <[email protected]> wrote: > Date: Sat, 25 Feb 2012 10:42:20 +0200 > From: Maris Nartiss <[email protected]> > Subject: Re: [GRASS-user] How to create polygon from two selected > contour line > To: Paolo Cavallini <[email protected]> > Cc: [email protected] > Message-ID: > <CAK8GbeCR-5p7QnTp6cQDLT16pZ=ymbrdsqpat73d+czbvwq...@mail.gmail.com> > Content-Type: text/plain; charset=UTF-8 > > Convert line type from line to boundary (v.type) > Digitize a pair of new boundaries between both contour lines to form a > enclosed area or use v.hull to get an outline for merging in (v.patch) > Add a centroid (digitize or v.centroids) to enclosed area. > Profit! > > Not the mos easy way, still possible. > > Maris. > > 2012/2/25 Paolo Cavallini <[email protected]>: >> Il 25/02/2012 08:45, SWAPAN GHOSH ha scritto: >> >>> Hello Grassuser, >>> Anybody can please help me " To create polygon from two selected contour >>> line " using grass comand.......... >> >> I'm afraid I can't - I tried recently, no joy. >> Good luck, if you succeed please let us know. >> All the best. >> >> -- >> Paolo Cavallini >> See: http://www.faunalia.it/pc >> >> _______________________________________________ >> grass-user mailing list >> [email protected] >> http://lists.osgeo.org/mailman/listinfo/grass-user > _____________________ C. Michael Barton Visiting Scientist, Integrated Science Program National Center for Atmospheric Research & University Consortium for Atmospheric Research 303-497-2889 (voice) Director, Center for Social Dynamics & Complexity Professor of Anthropology, School of Human Evolution & Social Change Arizona State University www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
