Dear Manuel, What is it about the map that looks wrong? What do you mean it has a "longitud 0" (the projected coordinates do not refer to longitude). Perhaps it is shifted in EW direction? Google (CRTM05) suggests that you need to use a false easting, +x_0=500000.
Robert On Thu, Oct 21, 2010 at 3:50 PM, Manuel Spínola <mspinol...@gmail.com> wrote: > Dear list members, > > I know that this is not a problem with the function, but I am trying to work > with CRTM05 (for Costa Rica) with these parameters ("+proj=tmerc +lon_0=-84 > +lat_0=0 +k=0.9999 +datum=WGS84") . I am trying to project a map in > geographic coordinates to CRTM05 but the projected map doesn't look right, > it has a longitud 0. > >> corr = readOGR(dsn="C:/ProyectoRespacial/EvalHab_reporte", > layer="corredor05unico") # en coordenadas geográficas > OGR data source with driver: ESRI Shapefile > Source: "C:/ProyectoRespacial/EvalHab_reporte", layer: "corredor05unico" > with 1 features and 4 fields > Feature type: wkbPolygon with 2 dimensions > >> corr.transf = spTransform(corr, CRS("+proj=tmerc +lon_0=-84 +lat_0=0 > +k=0.9999 +datum=WGS84")) # para CRTM05 >> writeOGR(corr.transf, > dsn="C:/ProyectoRespacial/CBSS/Shapefiles_proyectados", > layer="corredorCRTM05", driver="ESRI Shapefile") # para escribir el shape >> corre = readOGR(dsn="C:/ProyectoRespacial/CBSS/Shapefiles_proyectados", > layer="corredorCRTM05") > OGR data source with driver: ESRI Shapefile > Source: "C:/ProyectoRespacial/CBSS/Shapefiles_proyectados", layer: > "corredorCRTM05" > with 1 features and 4 fields > Feature type: wkbPolygon with 2 dimensions > >> proj4string(corre) > [1] " +proj=tmerc +lat_0=0 +lon_0=-84 +k=0.9999 +x_0=0 +y_0=0 +ellps=WGS84 > +datum=WGS84 +units=m +no_defs +towgs84=0,0,0" > > Am I missing some parameter to do the right projection? > Best, > > Manuel > > [[alternative HTML version deleted]] > > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@stat.math.ethz.ch > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > > _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo