pgirmess (version 1.6.9)

dirSeg: Computes segment directions.

Description

Computes the direction of segments from the first top clockwise (North = 0)

Usage

dirSeg(x,deg=TRUE)

Arguments

x

a matrix or data frame of 4 columns giving the coordinates of each segment tops x1, y1, x2, y2

deg

if TRUE (default) the output is in degrees, otherwise in radians

Value

A vector of directions

Details

The first two colomns give the first top coordinates, x then y, and the next two the second top coordinates.

See Also

dirProj, gzAzimuth

Examples

# NOT RUN {
x2<-rnorm(10)
y2<-rnorm(10)
mydata<-cbind(0,0,x2,y2)
dirs<-dirSeg(mydata)
dirs

plot(range(mydata[,c(1,3)]),range(mydata[,c(2,4)]),type="n")
Segments(mydata)
text(mydata[,3],mydata[,4],paste(round(dirs,0),"\u00b0"),cex=0.7)
  
# }