rectPERIM {GEOmap} | R Documentation |
Extract a rectangular perimeter
Description
Extract a rectangular perimeter
Usage
rectPERIM(x, y = 1, pct = 0)
Arguments
x |
x values or a list include x, y members |
y |
y values, if missing, x must be a list |
pct |
Percent expansion, based on range of x and y values. If pct>1 it is divided by 100 to get a fractional percent expansion. |
Details
The rectangular box will be expanded based on the percent pct.
Value
list of x, y values from lower left corner counter clockwise around perimeter
Author(s)
Jonathan M. Lees<jonathan.lees@unc.edu>
See Also
getGEOperim
Examples
fx =rnorm(20)
fy = rnorm(20)
plot(fx, fy, xlim=c(-4, 4), ylim=c(-4,4))
rp = rectPERIM(fx, fy)
polygon(rp)
text(rp, labels=1:4, pos=c(1,1,3,3), font=2, cex=2)
fx2 =rnorm(20, m=-1)
fy2 = rnorm(20, m=-1)
Fx = list(x=fx2, y=fy2)
points(Fx$x, Fx$y, col='red')
rp = rectPERIM(Fx)
polygon(rp, border='red')
######## try expanding the perim:
plot(fx, fy, xlim=c(-4, 4), ylim=c(-4,4), asp=1)
rp = rectPERIM(fx, fy, pct=0.1)
polygon(rp)
rp = rectPERIM(fx, fy, pct=0.2)
polygon(rp)
[Package GEOmap version 2.5-11 Index]