Sure. The ticket can be found here: https://trac.osgeo.org/gdal/ticket/3715
~James On Mon, Aug 09, 2010 at 03:13:59PM -0400, Lucena, Ivan wrote: > James, > > Could do file a ticked and upload a sample file on > http://trac.osgeo.org/gdal/ ? > > Regards, > > Ivan > > James Hiebert wrote: > > Hi All, > > > > I'm trying to use GDAL (version 1.7.2 on Gentoo built with hdf5 and netcdf > > support) to read NetCDF files, but I'm a little unclear on how the NetCDF > > driver attempts to determine the georeferencing. > > > > The driver page here: > > http://www.gdal.org/frmt_netcdf.html > > states that it will attempt to read the metadata "spatial_ref" for a Well > > Know Text definition of the spatial reference (I assume that it means that > > it will try to use a global attribute of the NetCDF file named spatial_ref). > > > > Since this would be convenient for my application, I attempted to use GDAL > > this way without success. > > > > + I added a global attribute named "spatial_ref" with the WKT definition of > > the spatial reference system. > > + gdalinfo on the file still reports "Coordinate System is `'" > > + opening the file with the python bindings and calling dst.GetProjection() > > returns a blank string (i.e. no projection information) > > > > The full listings of my spatial reference definition, the output of ncdump > > and gdalinfo and the output from the python session are listed below. Can > > anyone tell me whether I'm doing something wrong, or should I not count on > > georeferencing being supported by the NetCDF driver? > > > > ~James > > > > ja...@basalt ~ $ ncatted -a > > spatial_ref,global,a,c,'PROJCS["unnamed",GEOGCS["Normal Sphere > > (r=6370997)",DATUM["unknown",SPHEROID["sphere",6370997,0]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433]],PROJECTION["Polar_Stereographic"],PARAMETER["latitude_of_origin",60],PARAMETER["central_meridian",263],PARAMETER["scale_factor",1],PARAMETER["false_easting",3925000],PARAMETER["false_northing",8325000]]' > > narccap_ecpc-20c3m-tasmin-ncep.nc narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc > > > > > > ja...@basalt ~ $ ncdump -h narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc > > netcdf narccap_ecpc-20c3m-tasmin-ncep-with-srs { > > dimensions: > > xc = 123 ; > > yc = 104 ; > > time = UNLIMITED ; // (9496 currently) > > bnds = 2 ; > > variables: > > char polar_stereographic ; > > polar_stereographic:grid_mapping_name = > > "polar_stereographic" ; > > polar_stereographic:longitude_of_central_meridian = 263. ; > > polar_stereographic:straight_vertical_longitude_from_pole = > > 263. ; > > polar_stereographic:standard_parallel = 60. ; > > polar_stereographic:TrueGridLength_Latitude = 60. ; > > polar_stereographic:XGridLength_M = 50000. ; > > polar_stereographic:YGridLength_M = 50000. ; > > polar_stereographic:PoleOnPlane = "north" ; > > polar_stereographic:false_easting = 3925000. ; > > polar_stereographic:false_northing = 8325000. ; > > polar_stereographic:latitude_of_projection_origin = 90. ; > > double yc(yc) ; > > yc:long_name = "y-coordinate of Cartesian system" ; > > yc:standard_name = "projection_y_coordinate" ; > > yc:axis = "Y" ; > > yc:units = "m" ; > > double xc(xc) ; > > xc:long_name = "x-coordinate of Cartesian system" ; > > xc:standard_name = "projection_x_coordinate" ; > > xc:axis = "X" ; > > xc:units = "m" ; > > double lon(yc, xc) ; > > lon:units = "degrees_east" ; > > lon:long_name = "longitude" ; > > lon:standard_name = "longitude" ; > > lon:axis = "X" ; > > lon:NX_NumPntsOnParallel = 123 ; > > lon:NY_NumPntsOnMeridian = 104 ; > > lon:actual_range = 211.5412f, 316.2759f ; > > lon:XGridLength_M = 50000. ; > > lon:YGridLength_M = 50000. ; > > lon:PoleOnPlane = "north" ; > > double lat(yc, xc) ; > > lat:units = "degrees_north" ; > > lat:long_name = "latitude" ; > > lat:standard_name = "latitude" ; > > lat:axis = "Y" ; > > lat:NX_NumPntsOnParallel = 123 ; > > lat:NY_NumPntsOnMeridian = 104 ; > > lat:actual_range = 21.23807f, 67.63758f ; > > lat:XGridLength_M = 50000. ; > > lat:YGridLength_M = 50000. ; > > lat:PoleOnPlane = "north" ; > > ... > > > > // global attributes: > > ... > > :history = "Mon Aug 9 13:44:50 2010: ncatted -a > > spatial_ref,global,a,c,PROJCS[\"unnamed\",GEOGCS[\"Normal > > Sphere > > > > (r=6370997)\",DATUM[\"unknown\",SPHEROID[\"sphere\",6370997,0]],PRIMEM[\"Greenwich\",0],UNIT[\"degree\",0.0174532925199433]],PROJECTION[\"Polar_Stereographic\"],PARAMETER[\"latitude_of_origin\",60],PARAMETER[\"central_meridian\",263],PARAMETER[\"scale_factor\",1],PARAMETER[\"false_easting\",3925000],PARAMETER[\"false_northing\",8325000]] > > narccap_ecpc-20c3m-tasmin-ncep.nc > > narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc\n", > > "Fri May 8 09:34:14 2009: ncrcat > > tasmin_ECPC_1979010106.nc tasmin_ECPC_1981010106.nc > > tasmin_ECPC_1986010106.nc tasmin_ECPC_1991010106.nc > > tasmin_ECPC_1996010106.nc tasmin_ECPC_2001010106.nc > > narccap_ecpc-20c3m-tasmin-ncep.nc" ; > > :nco_openmp_thread_number = 1 ; > > :spatial_ref = "PROJCS[\"unnamed\",GEOGCS[\"Normal Sphere > > (r=6370997)\",DATUM[\"unknown\",SPHEROID[\"sphere\",6370997,0]],PRIMEM[\"Greenwich\",0],UNIT[\"degree\",0.0174532925199433]],PROJECTION[\"Polar_Stereographic\"],PARAMETER[\"latitude_of_origin\",60],PARAMETER[\"central_meridian\",263],PARAMETER[\"scale_factor\",1],PARAMETER[\"false_easting\",3925000],PARAMETER[\"false_northing\",8325000]]" > > ; > > } > > > > ja...@basalt ~ $ gdalinfo narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc > > Driver: netCDF/Network Common Data Format > > Files: narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc > > narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc.aux.xml > > Size is 512, 512 > > Coordinate System is `' > > Metadata: > > ... > > NC_GLOBAL#history1=Original output in GRIB 1 > > NC_GLOBAL#history2=Contains modifications made to original data > > NC_GLOBAL#history=Mon Aug 9 13:44:50 2010: ncatted -a > > spatial_ref,global,a,c,PROJCS["unnamed",GEOGCS["Normal Sphere > > > > (r=6370997)",DATUM["unknown",SPHEROID["sphere",6370997,0]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433]],PROJECTION["Polar_Stereographic"],PARAMETER["latitude_of_origin",60],PARAMETER["central_meridian",263],PARAMETER["scale_factor",1],PARAMETER["false_easting",3925000],PARAMETER["false_northing",8325000]] > > narccap_ecpc-20c3m-tasmin-ncep.nc > > narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc > > Fri May 8 09:34:14 2009: ncrcat tasmin_ECPC_1979010106.nc > > tasmin_ECPC_1981010106.nc tasmin_ECPC_1986010106.nc > > tasmin_ECPC_1991010106.nc tasmin_ECPC_1996010106.nc > > tasmin_ECPC_2001010106.nc narccap_ecpc-20c3m-tasmin-ncep.nc > > NC_GLOBAL#nco_openmp_thread_number=1 > > NC_GLOBAL#spatial_ref=PROJCS["unnamed",GEOGCS["Normal Sphere > > (r=6370997)",DATUM["unknown",SPHEROID["sphere",6370997,0]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433]],PROJECTION["Polar_Stereographic"],PARAMETER["latitude_of_origin",60],PARAMETER["central_meridian",263],PARAMETER["scale_factor",1],PARAMETER["false_easting",3925000],PARAMETER["false_northing",8325000]] > > Subdatasets: > > SUBDATASET_1_NAME=NETCDF:"narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc":lon > > SUBDATASET_1_DESC=[104x123] longitude (64-bit floating-point) > > SUBDATASET_2_NAME=NETCDF:"narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc":lat > > SUBDATASET_2_DESC=[104x123] latitude (64-bit floating-point) > > > > SUBDATASET_3_NAME=NETCDF:"narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc":time_bnds > > SUBDATASET_3_DESC=[9496x2] time_bnds (64-bit floating-point) > > > > SUBDATASET_4_NAME=NETCDF:"narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc":tasmin > > SUBDATASET_4_DESC=[9496x104x123] air_temperature (32-bit floating-point) > > Corner Coordinates: > > Upper Left ( 0.0, 0.0) > > Lower Left ( 0.0, 512.0) > > Upper Right ( 512.0, 0.0) > > Lower Right ( 512.0, 512.0) > > Center ( 256.0, 256.0) > > > > > > ja...@basalt ~ $ python > >>>> from osgeo import gdal > >>>> dst = gdal.Open("narccap_ecpc-20c3m-tasmin-ncep-with-srs.nc") > >>>> dst.GetProjection() > > > > _______________________________________________ > > gdal-dev mailing list > > [email protected] > > http://lists.osgeo.org/mailman/listinfo/gdal-dev > > > _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
