R: Explode Points

explode {GEOmap} | R Documentation

## 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<jonathan.lees@unc.edu>

### 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)

[Package GEOmap version 2.4-0 Index]