[Proj] Using Azimuthal Equidistant for Great/Small Circle Generation

Gerald I. Evenden gerald.evenden at verizon.net
Wed Mar 8 15:54:46 EST 2006

On Wednesday 08 March 2006 01:26 pm, Rob Iverson wrote:
> Sorry for the nearly-off-topic message here!  I don't know where else to
> turn...
> Is it valid to use the two-hemisphere form of the Azimuthal Equidistant
> projection to compute great circles and small circles?


The only projection where straight lines are great circles is the gnomonic but 
I don't think you want to use that one.

The program 'geod' distributed with the old PROJ4 system computes geodesics 
(great circles) and will generate intermediate points along such paths or 
points on a arc that are at a constant distance from a point.

'geod' works for both a spherical  or  elliptical earth.

Jerry and the low riders:Daisy May and Joshua
"The being cannot be termed rational or virtuous,
who obeys any authority, but that of reason."
---Mary Wollstonecraft 1792

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