GEOmap (version 2.5-11)

GEOTOPO: Topographic Plot of geographic region

Description

Extract subset of a topographic database, interpolate and plot using the persp program.

Usage

GEOTOPO(TOPO, PLOC, PROJ, calcol=NULL, nx=500, ny=500, nb = 4, mb = 4, hb = 8, PLOT=TRUE)

Value

PMAT

Matrix from persp, used for adding other geographic information

xo

x-coordinates

yo

y-coordinates

IZ

interpolated elevations

Cmat

matrix of RGB Colors

Dcol

dimensions of Cmat

Arguments

TOPO

list of x,y,z for a DEM

PLOC

Location list, includes vectors LON and Lat

PROJ

projection

calcol

color table for coloring elevations above sea level

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

PLOT

logical, TRUE=plot a map and return color map

Author

Jonathan M. Lees<jonathan.lees.edu>

Details

The return matrix PMAT is a rotation matrix used for adding geographic (projected) data onto the perspective plot.

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

See Also

subsetTOPO, TOPOCOL, LandSeaCol, settopocol, subsetTOPO, persp, DOTOPOMAPI

Examples

if (FALSE) {

library(geomapdata)

####  need to download and install ETOPO data
###   data(ETOPO5)
load(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) )
COLS = settopocol()
JMAT = GEOTOPO(ETOPO5, PLOC, PROJ, COLS$calcol, nx=1000, ny=1000, nb=8, mb=8, hb=12, PLOT=TRUE)

############  this plot can be duplicated by using the output or GEOTOPO


 PMAT = persp(JMAT$xo, JMAT$yo, JMAT$IZ$z, theta = 0, phi = 90, r=4000,
col=JMAT$Cmat[1:(JMAT$Dcol[1]-1), 1:(JMAT$Dcol[2]-1)] , scale = FALSE,
      ltheta = 120, lphi=60, shade = 0.75, border = NA, expand=0.001, box = FALSE )


}