Example 5.10. British National Grid
int crs ;
crs:grid_mapping_name = "transverse_mercator";
crs:semi_major_axis = 6377563.396 ;
crs:semi_minor_axis = 6356256.910 ;
crs:inverse_flattening = 299.3249646 ;
crs:latitude_of_projection_origin = 49.0 ;
crs:longitude_of_projection_origin = -2.0 ;
crs:false_easting = 400000.0 ;
crs:false_northing = -100000.0 ;
crs:scale_factor_at_projection_origin = 0.9996012717 ;
but Appendix F has:
Transverse Mercator
grid_mapping_name = transverse_mercator
Map parameters:
scale_factor_at_central_meridian
longitude_of_central_meridian
latitude_of_projection_origin
false_easting
false_northing
I think we can presume that
scale_factor_at_central_meridian == scale_factor_at_projection_origin
longitude_of_central_meridian == longitude_of_projection_origin
central_meridian is probably clearer; so maybe just update the example ??
or we can add this amendment to ticket #75= "fix documentation and
definitions of 3 grid mapping definitions"
_______________________________________________
CF-metadata mailing list
CF-metadata@cgd.ucar.edu
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata