rotate: Rotate Points

Description

Rotate a set of points.

Usage

rotate (object, degrees, centrexy = NULL, ...)

Arguments

object

object that may be coerced to a numeric matrix

degrees

clockwise angle of rotation in degrees

centrexy

vector with xy coordinates of rotation centre

...

other arguments (not used)

Value

A matrix with the location of each point rotated about the centre.

Details

The first column of object holds the x coordinates of the points and the second holds the y coordinates. If centrexy is NULL then rotation is about (0,0). A generic method, introduced for the class-specific method rotate.traps.

Examples

Run this code

temp <- matrix(runif (20) * 2 - 1, nc = 2)
temp2 <- rotate(temp, 25)
plot(temp, xlim=c(-1.5,1.5), ylim = c(-1.5,1.5), pch = 16)
points (0,0, pch=2)
points (temp2, pch = 1)
arrows (temp[,1], temp[,2], temp2[,1], temp2[,2], length = 0.1)