[Proj] Projection conversion problem

Andre Joost andre+joost at nurfuerspam.de
Thu Jun 30 11:16:43 EST 2016


Am 30.06.2016 um 13:24 schrieb Andre Joost:
> Am 30.06.2016 um 10:20 schrieb Damian Rakowski:
>> That  looks very interesting, thank you for your reply. One more
>> question: 6371000 - this is an Earth radius0.0093202511 - how did you
>> got this value? I just want to understand :) Best Regards, Damian
>>

>
>   From John P. Snyders "Map Projections - A Working Manual" p.91, you can
> take the exact formulas for the sphere:
>
> x = R (lambda-lambda0) cos phi1
> y = R phi
>
> with angles in radians. This is linear to the angles, and you just have
> to compare them with your scale factor.
>

So my to_meter factor is:

PI() * 6371000 / 2^31 = 0.009320251

Greetings,
André Joost




More information about the Proj mailing list