[Proj] Some questions

support.mn at elisanet.fi support.mn at elisanet.fi
Sat Apr 4 08:51:06 EST 2009

I understand. The problem for our part is that we are seeking
all the time more and more accuracy. Could we put it behind
some switch? The standard version would not allow such
parameters, but if one switched some switch on, then one
could use such parameters.

Something like:


The full control of the calculation is important for us since we have
to get accurate results (especially in the future). If it is behind some
switch, that does not bother us? The other people will also not
see any difference, since the switch could be off by default.

Regards: Janne. / MNS Support


> > For example something like:
> > 
> > pellps=.....
> > dellps=.....
> > 
> > where "pellps" would stand for "projection ellipsoid" and
> > "dellps" for "datum ellipsoid".
> > 
> > and when both are the same, just normal
> > 
> > ellps=....
> > 
> > where "ellps" stands for both datum and projection. That
> > would not alter the existing definitions, but allow more
> > accurate control of the ellipsoids involved.

> No, no such capability has been implemented.  I'm still not too keen
> on doing so either for reasons previously stated.

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