[OSRS-PROJ] towgs84

[Frank Warmerdam]

Igor Alfirevic wrote:
> Hi!
> 
> If i include paramter +towgs84 in proj.exe
> ther is no efect. Why??
> 
> 
> proj +proj=utm +ellps=intl +towgs=100,200,300 +zone=33

Igor,

The proj program specifically converts between a projection and the
lat/long coordinates on the same ellipsoid.  It ignores any "auxilary"
information like datum or prime meridian.  So the +towgs84 information is
not significant since it never attempts to convert to/from wgs84.

As I presume you have since discovered, the cs2cs program is more appropriate
for conversion between arbitrary coordinates systems.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent

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