subsetTOPO {GEOmap}

Subset a Topo map

Description

Extract a subset of a topo DEM

Usage

subsetTOPO(TOPO, ALOC, PROJ, nx=500, ny=500, nb = 4, mb = 4, hb = 8)

Arguments

TOPO

DEM list including x,y,z

ALOC

list including LAT LON vectors for extracting an array from the DEM

PROJ

projection

nx

number of points in x grid, default=500

ny

number of points in y grid, default=500

nb

see function mba.surf, default = 4

mb

see function mba.surf, default = 4

hb

see function mba.surf , default= 8

Details

Used 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

Value

x

vector x-coordinates

y

vector y-coordinates

z

2D matrix of elevations

Author(s)

Jonathan M. Lees<jonathan.lees.edu>

See Also

GEOTOPO

Examples

## 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)