[Proj] pj_transform function

Frank Warmerdam warmerdam at pobox.com
Fri Oct 6 11:03:06 EDT 2006


Sandeep Kumar Jakkaraju wrote:
> Hi All
>  
>  
> I want to transform ... this lat/lon 39.739/-104.985...
>  
> to world mercator project ..with the defintition
>  
> 
> World Mercator <54004> +proj=merc +latts=0 +lon0=0 +k=1.000000 +x0=0 
> +y0=0 +ellps=WGS84 +datum=WGS84 +units=m no_defs <>
> 
>  but the method gives an "error"....
> 
> this method works fine if i give lat/lon say 42.4182,-74.2643
> 
> can some one help me ... Doesnt this pj_transform always work !!!

Sandeep,

I expect the problem has to do with axis order.  By default proj
expects geographic locations in "longitude latitude" order.  So
you need to pass -104.985 39.729.

If -104 is treated as a latitude it will be beyond the legal range
(-90 to 90).

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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