[Proj] Re: Extracting the to_meter parameter from a projection

Gerald I. Evenden gerald.evenden at verizon.net
Tue Nov 15 19:26:28 EST 2005


One thing to remember with proj AND libproj4 is that neither  care
about units.  Units depend upon the units that define +a (and +b, x_0,
etc.).  All prestored constants for radius or elliptic axis are presented in
meters which is the factor that to_/fr_meter depends upon.

--> IF the user defines +a= in feet, then to_/fr_meter is meaningless and
should not be used and Easting/Northing will be in feet.

As I recall, this material is discussed in the first proj manual.

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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