trans2seg {pgirmess}

Convert a transect coordinate file into a matrix with segment coordinates.

Description

Convert a transect coordinate file (e.g.: waypoints) into a matrix with segment coordinates.

Usage

trans2seg(vect)

Arguments

vect

A two column matrix or data.frame

Details

The argument passed is a matrix or data.frame of two columns each row is a transect interval; each column must start (first row) and end (last row) with a landmark ; intermediate waypoints must have coordinates in the two columns of the row. Other rows must be NA values.

Value

A matrix of 4 columns to be passed e.g. to functions as "segments".

See Also

trans2pix

Examples

x<-c(10,NA, NA, NA,56,NA,NA,100)
y<-c(23,NA, NA, NA,32,NA,NA,150)
cols=c("red","blue","blue","blue","red","blue","blue","red")
plot(x,y,col=cols,pch=19)
mysegs<-trans2seg(cbind(x,y))
segments(mysegs[,1],mysegs[,2],mysegs[,3],mysegs[,4])