[Gdal-dev] simple OGR/python projection question

[John C Cartwright]

Hello All,

I'm using the OGR python bindings to convert Plate 
Carree(Equirectangular) coordinates in meters to geographic coordinates 
in WGS84.  I'm getting an answer like:

(-104.99999999546829, 38.999751150159064, 8426.3269814412379)

I understand that the first two values are longitude and latitude, but I 
don't understand the third term. Can some one explain?

Code fragment listed below.

Thanks!

-- john




wkt = 'PROJCS["World_Plate_Carree", GEOGCS["WGS 84", DATUM["WGS_1984", 
SPHEROID["WGS_1984", 6378137.0, 298.257223563]], PRIMEM["Greenwich", 
0.0], UNIT["degree",0.017453292519943295]], 
PROJECTION["Equirectangular"], PARAMETER["false_easting",  0.0], 
PARAMETER["false_northing", 0.0], PARAMETER["Central_Meridian", -180.0], 
UNIT["Meter",1.0]]'

sourceSrs = osr.SpatialReference()
targetSrs = osr.SpatialReference()
sourceSrs.ImportFromWkt(wkt)
targetSrs.ImportFromEPSG(4326)
transform = osr.CoordinateTransformation(sourceSrs,targetSrs)
coords = transform.TransformPoint(x,y)
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