[Proj] Fw: postgis-users Digest, Vol 98, Issue 6

[Stephane Poirier]

Hi All,

How can I determine the proper PROJ4 parameters considering I have the 
following projection parameters for my data files (see PARAM for the North 
American CRCM grid herein below my signature)? Is it documented somewhere 
within POSTGIS documentation? Or somewhere within PROJ4 documentation?

Here's the best hack I can come up with for the PROJ4 definition: 
Proj4js.defs["SR-ORG:6728"]="+proj=stere +lat_0=49.65698 +lat_ts=60 
+lon_0=-96.99443 +k=1 +x_0=-1300000 +y_0=100000 +ellps=WGS84 +datum=WGS84 
+units=m +no_defs"; But it is not valid. Need some help in adjusting these 
parameters. Are the basics PROJ4 parameters documented somewhere?.

Stephane

--------------------------------------------------------------------
Stephane Poirier, M.Sc. Optical Physics
Remote Sensing Application Software Developer
Geography Department, Burnside Hall
McGill University, Montreal, QC, Canada
http://geog.mcgill.ca
Stephane.Poirier2 at mcgill.ca
Cell. (514) 994-3532
Fax: (514) 509-8833
--------------------------------------------------------------------



PARAM for the North American Canadian Regional Climate Model (CRCM) grid:
"
     float yc(yc) ;
               yc:units = "m" ;
               yc:long_name = "y-coordinate of polar-stereographic
projection" ;
               yc:standard_name = "projection_y_coordinate" ;
               yc:axis = "y" ;
               yc:coordinate_defines = "point" ;
               yc:actual_range = 22500.f, 7807500.f ;
       float xc(xc) ;
               xc:units = "m" ;
               xc:long_name = "x-coordinate of polar-stereographic
projection" ;
               xc:standard_name = "projection_x_coordinate" ;
               xc:axis = "x" ;
               xc:coordinate_defines = "point" ;
               xc:actual_range = 22500.f, 8167500.f ;
           float lon(yc, xc) ;
               lon:units = "degrees_east" ;
               lon:long_name = "longitude" ;
               lon:standard_name = "longitude" ;
               lon:actual_range = 160.4761f, 332.2443f ;
       float lat(yc, xc) ;
               lat:units = "degrees_north" ;
               lat:long_name = "latitude" ;
               lat:standard_name = "latitude" ;
               lat:actual_range = 11.56135f, 87.47531f ;
       char polar_stereographic ;
               polar_stereographic:straight_vertical_longitude_from_pole =
245.f ;
               polar_stereographic:standard_parallel = 60.f ;
               polar_stereographic:false_easting = -2790000.f ;
               polar_stereographic:false_northing = -8113500.f ;
               polar_stereographic:hemisphere_of_standard_parallel = 1.f ;
               polar_stereographic:resolution_at_standard_parallel = 45000.f
;
"


Stephane