Dear all, during kernel LSCV calculation for home range estimation (kernelUD, package adehabitat) I encountered a problem related to topology. One homerange is made of 5 polygons, but one of them has a null area: it is in fact a little line. The other polygons have some dangling arcs. R displays the homerange without warnings, then exports it as shapefile. As the shapefile is imported into a Postgis database, the wrong topology becomes a serious problem. I know that topology operations are typical GIS tasks. Could it be useful to add to R functions basic tools like clean/build topology of its spatial objects, even if it causes code duplication (in fact R spatial objects are quite always imported into a GIS)? All the best, Anne Ghisla Universit? dell'Insubria, Varese
Cleaning topology in R spatial objects - R or GIS task?
2 messages · Anne Ghisla, Dylan Beaudette
On Friday 07 December 2007 05:20:59 am Anne Ghisla wrote:
Dear all, during kernel LSCV calculation for home range estimation (kernelUD, package adehabitat) I encountered a problem related to topology. One homerange is made of 5 polygons, but one of them has a null area: it is in fact a little line. The other polygons have some dangling arcs. R displays the homerange without warnings, then exports it as shapefile. As the shapefile is imported into a Postgis database, the wrong topology becomes a serious problem. I know that topology operations are typical GIS tasks. Could it be useful to add to R functions basic tools like clean/build topology of its spatial objects, even if it causes code duplication (in fact R spatial objects are quite always imported into a GIS)? All the best, Anne Ghisla Universit? dell'Insubria, Varese
GRASS is an excellent platform for this type of operation. Cheers, Dylan