cwhmisc (version 6.0)

lowess.bygroup: Plot data in groups, each group with separate lowess smoothing

Description

data in groups (shown by variable group) are plotted

Usage

lowess.bygroup(x, y, group, span=2/3, col=seq_along(x), lty=seq_along(x))

Arguments

x, y

coordinate vectors of equal length

group

grouping variable, must be a vector of same length as x and y

span

span of smooting

col

colour of lines

lty

line type

Value

The procedure is called for its side effect of producing a plot

Examples

  par(mfrow=c(1,1))
  gr <- c(rep(1,20),rep(2,30),rep(3,50))
  x <- seq_along(gr); y <- jitter(0.01*(x-50)^2 + 1,1000)
  plot(x,y,pch=".",cex=4,xlab="Lowess, with spans = 0.2 (r,g,mag), 0.4 (blue) ")
  lowess.bygroup(x,y,gr,span=0.2,col=c("red","green","magenta"),lty=rep(2,3))
  lowess.bygroup(x,y,gr,span=0.4,col="blue")