[Proj] Problems with /Op option used to compile proj in Microsoft Visual Studio

Calogero Mauceri mauceri at actgate.com
Tue Mar 20 12:09:13 EST 2012

Sorry for replying so late, but I've been quite busy lately.

Frank Warmerdam wrote:
> I don't claim to understand the tpeqd projection well, but your parameters:
>   +lat_1=-22.960070000 +lon_1=65.546300000
>   +lat_2=-22.959730000 +lon_2=65.546160000
> seem suspect to me in that they are so close.  Do you find similar
> stability issues when the two points used are not so very close
> together?

Unfortunately we are mostly using the tpeqd projection with the two 
points very close. We need minimal distortion between the reference points.

Glynn Clements wrote:
> IOW, the formulation used is going to be unstable when the angle
> between the reference points is small.

Glynn, thank you very much for your explanation. So the smaller is the 
distance between the two points of the tpeqd, then the less accurate are 
the conversions. Those are really bad news :(.


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