Subset a Topo map
Extract a subset of a topo DEM
subsetTOPO(TOPO, ALOC, PROJ, nx=500, ny=500, nb = 4, mb = 4, hb = 8)
TOPO
: DEM list including x,y,zALOC
: list including LAT LON vectors for extracting an array from the DEMPROJ
: projectionnx
: number of points in x grid, default=500ny
: number of points in y grid, default=500nb
: see function mba.surf, default = 4mb
: see function mba.surf, default = 4hb
: see function mba.surf , default= 8Used for extracting a subset of ETOPO5 or ETOPO2.
ETOPO5 or ETOPO2 can be downloaded from and installed using these links: http://leesj.sites.oasis.unc.edu/FETCH/GRAB/RPACKAGES/ETOPO2.RData
and http://leesj.sites.oasis.unc.edu/FETCH/GRAB/RPACKAGES/ETOPO5.RData
x: vector x-coordinates
y: vector y-coordinates
z: 2D matrix of elevations
Jonathan M. Lees<jonathan.lees.edu>
GEOTOPO
## Not run: #### first install the ETOPO5 data package library(geomapdata) load(ETOPO5) ## data(ETOPO5) PLOC=list(LON=c(137.008, 141.000),LAT=c(34.000, 36.992), x=c(137.008, 141.000), y=c(34.000, 36.992) ) PROJ = setPROJ(type=2, LAT0=mean(PLOC$y) , LON0=mean(PLOC$x) ) JAPANtopo = subsetTOPO(ETOPO5, PLOC, PROJ) ## End(Not run)
Useful links