Justin, Paul's suggestion is spot on. I'd add that www.spatialreference.org is a handy web api for that same trick.
You can plug your some of your .prj text in the search like: http://www.spatialreference.org/ref/epsg/?search=NAD_1983_StatePlane_Maryland_FIPS_1900_Feet&srtext=Search+EPSG+References and get back: http://www.spatialreference.org/ref/epsg/102685/ or http://www.spatialreference.org/ref/epsg/102685/proj4/ -dane On May 21, 2008, at 10:19 AM, Paul Smith wrote: > On Wed, May 21, 2008 at 12:08 PM, Justin Palk <[EMAIL PROTECTED]> > wrote: >> Layer SRS WKT: >> PROJCS["NAD_1983_StatePlane_Maryland_FIPS_1900_Feet", >> GEOGCS["GCS_North_American_1983", >> DATUM["North_American_Datum_1983", >> SPHEROID["GRS_1980",6378137.0,298.257222101]], >> PRIMEM["Greenwich",0.0], >> UNIT["Degree",0.0174532925199433]], >> PROJECTION["Lambert_Conformal_Conic_2SP"], >> PARAMETER["False_Easting",1312333.333333333], >> PARAMETER["False_Northing",0.0], >> PARAMETER["Central_Meridian",-77.0], >> PARAMETER["Standard_Parallel_1",38.3], >> PARAMETER["Standard_Parallel_2",39.45], >> PARAMETER["Latitude_Of_Origin",37.66666666666666], >> UNIT["Foot_US",0.3048006096012192]] > >> m = Map(1024,1024,"+proj=lcc +datum=NAD83") > > I suspect that the 'srs' argument to the Map constructor does not give > in the same spatial ref sys as the shapefile's. Running the WKT of the > shapefile's SRS through ogr.osr.SpatialReference's ExportToProj4(): > > '+proj=lcc +lat_1=38.3 +lat_2=39.45 +lat_0=37.66666666666666 > +lon_0=-77 +x_0=399999.9999999999 +y_0=0 +ellps=GRS80 +datum=NAD83 > +to_meter=0.3048006096012192 +no_defs ' > > Cheers, > Paul. > > -- > Paul Smith > http://www.pauladamsmith.com/ > _______________________________________________ > Mapnik-users mailing list > [email protected] > https://lists.berlios.de/mailman/listinfo/mapnik-users _______________________________________________ Mapnik-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/mapnik-users
