explode: Explode Points

In GEOmap: Topographic and Geologic Mapping

Explode Points

Description

Explode a set of points away from a center point

Usage

explode(fxy, dixplo=1, mult=1, cenx=0, ceny=0, PLOT=FALSE)

Arguments

fxy	list of x, y coordinates
dixplo	distance to explode
mult	multiplier for the distance
cenx	x coordinate center of explosion
ceny	y coordinate center of explosion
PLOT	logical, TRUE=make a plot of the resulting explosion

Details

If cenx and ceny is missing it is assumed to be the mean of the coordinates. Program calculates the new locations radiating away from the central point. No protection against overlapping symbols is included.

Value

list of new x,y values

x	new x coordinates
y	new y coordinates

Author(s)

Jonathan M. Lees<[e-mail]>

See Also

ExplodeSymbols, NoOverlap

Examples

############  random data
x = rnorm(20)
y = rnorm(20)

NEW = explode(list(x=x,y=y), dixplo =1)

plot(range(c(x,NEW$x)), range(c(y,NEW$y)), asp=1, type='n')
segments(x,y,NEW$x, NEW$y)
points(x,y, pch=3, col='red')
points(NEW$x, NEW$y, pch=6, col='blue', cex=2)


###  try a larger radius:
NEW2 = explode(list(x=x,y=y), dixplo =1.3)
points(NEW2$x, NEW2$y, pch=7, col='brown', cex=2, xpd=TRUE)
arrows(NEW$x, NEW$y,NEW2$x, NEW2$y, col='green' )



#####   try with a different center
cenx=-1; ceny=-1
NEW = explode(list(x=x,y=y), dixplo =1, cenx=cenx, ceny=ceny)
plot(range(c(x,NEW$x)), range(c(y,NEW$y)), asp=1, type='n')
points(x,y, pch=3, col='red')
segments(x,y,NEW$x, NEW$y)
points(NEW$x, NEW$y, pch=6, col='blue', cex=2)
points(cenx, ceny, pch=8, col='purple')
text(cenx, ceny, labels="Center Point", pos=1)

GEOmap documentation built on Sept. 1, 2023, 5:09 p.m.