Shapefile

Contour lines - an update

The whole thing is actually a lot less complicated than previously posted.
In fact, gvSIG does the job really nicely. Follow the series of screenshots below and produce some lovely contour lines.



Add your points to a view. Open the Sextante tool and select "inverse distance". 

Select the correct field (spot the mistake - It's "elevation", not "EASTING", view extent and raster output cell size. 




A raster image is produced on the elevation information attached to your points:




Now for the production of contour lines: Sextante - vectorisation - contour lines:




Make sure the equidistance selected is no smaller than the raster cell size defined above, otherwise you will end up with false results.

The output with the raster image displayed in the background:




Nice, clean contour lines:





...which can then be exported as shapefiles and added to any project. The elevation information is attached to each of them.

Posted at 05:50AM Oct 07, 2008 by Anna in General  |  Comments[1]