getETOPO {GEOmap} | R Documentation |
Get Subset ETOPO Digital elevation map
Description
Extract from ETOPO5 or ETOPO2 data a rectangular subset of the full data.
Usage
getETOPO(topo, glat = c(-90, 90), glon = c(0, 360))
Arguments
topo |
A DEM matrix, ETOPO5 or ETOPO2 |
glat |
2-vector, latitude limits |
glon |
2-vector, longitude limits (these are converted 0-360 |
Details
ETOPO2 and ETOPO5 are stored in a strange way: the lons are okay the latitudes are upside down.
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
Returns a matrix with attributes in lat-lon that are correct for usage in image or other R imaging programs.
Author(s)
Jonathan M. Lees<jonathan.lees@unc.edu>
See Also
image
Examples
## Not run:
library(geomapdata)
### Download and install ETOPO Data
## data(ETOPO5)
load(ETOPO5)
glat =c(45.4, 49)
glon = c(235, 243)
b5 = getETOPO(ETOPO5, glat, glon)
image(x=attr(b5, 'lon'), y=attr(b5,'lat'), z=b5, col=terrain.colors(100) )
contour( x=attr(b5, 'lon'), y=attr(b5,'lat'), z=b5, add=TRUE)
## End(Not run)
[Package GEOmap version 2.5-11 Index]