| setPROJ {GEOmap} | R Documentation |
Set Projection
Description
Setup parameters for Map Projection
Usage
setPROJ(type = 1, LAT0 = 0, LON0 = 0, LAT1 = 0, LAT2 = 0, LATS = NULL,
LONS = NULL, DLAT = NULL, DLON = NULL, FE = 0, FN = 0, IDATUM=1)
Arguments
type |
Type of projection |
LAT0 |
Central Latitude |
LON0 |
Central Longitude |
LAT1 |
Latitude parameter for special projection, where needed |
LAT2 |
Latitude parameter for special projection, where needed |
LATS |
vector of range of Latitudes |
LONS |
vector of range of Longitudes |
DLAT |
difference of Lats |
DLON |
difference of Lons |
FE |
False Easting |
FN |
False Northing |
IDATUM |
integer, index to the datum database |
Details
Set up for the various projections used by GEOmap
Value
List of values described above
Note
Some of the parameters are not critical to all the choices or Map Projection. In that case they are set to defaults and ignored by that projection.
LONs are modified and rectified by fmod function.
The datum data base is accesses via the function DATUMinfo. There are 11 different projection datums. These are NAD83/WGS84, GRS 80, WGS72, Australian 1965, Krasovsky 1940, International (1924) -Hayford (1909), Clake 1880, Clarke 1866, Airy 1830, Bessel 1841, Everest 1830.
Author(s)
Jonathan M. Lees<jonathan.lees.edu>
References
Snyder, John P., Map Projections- a working manual, USGS, Professional Paper, 1987.
See Also
projtype, XY.GLOB, GLOB.XY, DATUMinfo
Examples
###### type
projtype()
###### type = mercator spherical
setPROJ(type = 1, LAT0 =23, LON0 = 35)
### Hengill Map: lambert.cc
setPROJ(type=3, LAT0=65, LON0=360-19 ,LAT1=64+15/60,
LAT2=65+45/60,LATS=NULL,
LONS=NULL, DLAT=NULL, DLON=NULL,FE=500000,FN=500000)
### old lees/crosson projection
setPROJ(type=99, LAT0=23, LON0=35, LATS=NULL, LONS=NULL, DLAT=NULL,
DLON=NULL, FN =0)
### world map equid.cyl
setPROJ(6, LAT0=0, LON0=0)
## North Carolina Map lambert.cc
setPROJ(type=3, LAT0=36+20/60, LON0=78+30/60,LAT1=36+46/60,
LAT2=37+58/60, LATS=NULL, LONS=NULL, DLAT=NULL, DLON=NULL,FE=0,FN=0)
### No Projection
setPROJ(type = 0, LAT0 =23, LON0 = 35)