adapting spatial points and wrld_smpl to a reference system implicit in a .nc file
On 02/22/2016 09:50 AM, Agus Camacho wrote:
Dear all, Im trying to overlap these points: https://www.dropbox.com/s/awdclg4cvsdngej/clean%20urosaurus%20records.csv?dl=0 and a wrld_simpl object: library(maptools) data(wrld_simpl) Over this raster layer https://www.dropbox.com/sh/qcw174tgogpnz7s/AAByDc3TeyFe3W4nEqTFix6Oa?dl=0 This rastr comes from a .nc file without a reference system. The author of that .nc file gave me the following data about the .nc. The projection is *Lambert conformal conic* projection CEN_LAT = 38.0 CEN_LON = -100.0 TRUELAT1 = 25. TRUELAT2 = 45. However, despite i have gone through many sites in the internet, i cant figure it out: a) if that is all the data i need to set a reference system for my points and the wrld_simp object. b) how to change a typical CRS object with such data Ex.CRS ("+proj=lcc+lat_0=38.0+lon0_2=-100+ellps=WGS84") Where do i enter the TRUELAT and CENLAT values? Are there any site that explains easily what the fields in the CRS mean and how to change them? Thanks in advance.
https://github.com/OSGeo/proj.4/wiki/GenParms https://trac.osgeo.org/proj/wiki/GenParms I believe: +lat_0 = CEN_LAT Latitude of origin +lat_1 = TRUELAT1 Latitude of first standard parallel +lat_2 = TRUELAT2 Latitude of second standard parallel +lon_0 = CEN_LON Central meridian proj strings are defined by the proj4 libary. It's website listed above and the associated mailing lists or gis stackexchange would be the places to get help on it. https://lists.osgeo.org/mailman/listinfo/metacrs It often helps to browse similar projections on http://spatialreference.org/ http://epsg.io/ Enjoy, Alex