[FWTools] cs2cs problem

[Frank Warmerdam]

On 11-01-14 08:34 PM, Mikhail Tchernychev wrote:
>    Hello FWTools users,
>
> First of all, thank you for these wonderful tools.
>
> Here is my question: if I use cs2cs program from FWTools (2.4.7) shell
>
> C:\Program Files\FWTools2.4.7>cs2cs -I -f "%.10f" +from +proj=latlong
> +datum=WGS84
> +to +proj=latlong +ellps=krass
> +towgs84=43.82,-108.842,119.585,+1.455,-0.761,+0.737,+0.548
>
> I get the following (input / output)
>
> 50.7334137 45.5004868
> 50.7322097853   45.5020745895 158.7042389987
>
> If I use previous version
>
> C:\Program Files\FWTools2.4.3>cs2cs -I -f "%.10f" +from +proj=latlong
> +datum=WGS84
> +to +proj=latlong +ellps=krass
> +towgs84=43.82,-108.842,-119.585,+1.455,-0.761,+0.737,+0.548
>
> The results are:
>
> 50.7334137 45.5004868
> 50.7322097853   45.5005663276 -11.8877343033
>
> As you could see longitude is the same.
>
> I also tried proj which comes with QGis, as well as stand alone cygwin
> version. Second result appeared to be
> correct.

Mikail,

Indeed the results from FWTools 2.4.7 are wrong.  It appears no datum
shift is being applied, just a change of ellipsoid.  I don't know why
that is the case - modern cs2cs in OSGeo4W or on linux works as expected.

All I can think of is to produce a new FWTools with the latest PROJ.4.
It is possible you are seeing some sort of transitional bug that was
introduced and then fixed.  Since I have no immediate plans to produce
a new FWTools for windows release there isn't much to do but use another
version for now.

Best regards,



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