[Proj] WGS84 to ED50

[Paul Kelly]

On Thu, 29 Nov 2007, Roger Oberholtzer wrote:

[...]
> I have tried setting proj to use this, as reported earlier in this thread, with no luck. I tried using the 7 parameters as
> +towgs84=125.098545,76.000054,156.198703,0.0,0.0,-1.129,-8.30463103, but that made things worse.
>
> fromProj = pj_init_plus(
>                        "+proj=latlong "
>                        "+ellps=WGS84 "
>                        "+no_defs");
>
> toProj = pj_init_plus(
>                        "+proj=utm "
>                        "+ellps=intl "
>                        "+k=0.999600 "
>                        "+x_0=500000.0 "
>                        "+y_0=0.0 "
>                        "+zone=30 "
>                        "+units=m"
>
> "+towgs84=125.098545,76.000054,156.198703,0.0,0.0,-1.129,-8.30463103"
>                        "+no_defs");
>
> So I am guessing I cannot simply use the 7 parameters as given. Correct?

You haven't set datum parameters for the first co-ordinate system. You 
should try adding "+towgs84=0,0,0" to its definition.

Paul