[Proj] cs2cs's +towgs84 usage

[Ilumas]

Dear list,

could you kindly confirm that the cs2cs's +towgs84 parameters remain the
same for a certain datum regardless of the direction of the transformation.
Some people (e.g.
http://n2.nabble.com/Datum-Shift-WGS84-to-Arc1960-not-working-propberly-td3410479.html)
<http://n2.nabble.com/Datum-Shift-WGS84-to-Arc1960-not-working-propberly-td3410479.html>seem
to suggest that the values need to be negated when going FROM wgs84 TO
something else, but this seems a bit strange to me. Unfortunately all the
examples in the man pages seem to be about changing the coordinates TO
wgs84...

Thanks a lot in advance!

ilumas

<http://n2.nabble.com/Datum-Shift-WGS84-to-Arc1960-not-working-propberly-td3410479.html>
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