Set Various Map Constants
Used for retrieval when doing projections
MAPconstants()
These include a sime list of: DEG2RAD, RAD2DEG, A.MAPK, E2.MAPK, E2.GRS80, E.MAPK, E1.MAPK, TwoE.MAPK, R.MAPK, FEET2M, M2FEET
List of constants for Projections
Snyder, John P., Map Projections- a working manual, USGS, Professional Paper, 1987.
Jonathan M. Lees<jonathan.lees.edu>
XY.GLOB, projtype, utm.sphr.xy
MAPconstants()
Useful links