R: positioning of the legend and length of the lines in the legend

Question

I can't set the location of the legend properly, I have tried to play around with xjust and ncol but it still appears in the middle of the graphic.

Can you help it align it to the border (left or right I do not care)?

Moreover is it possible to draw shorter lines in the legend? These appear too long.

 par(mar=c(5,4,4,5)+.1)
 plot(1:109,rnorm(109), type="l",col="blue", lwd=2, 
      main="Compare signal and std deviation MC3 ch44",
      ylab="signal", xlab="locations")
 par(new=TRUE)
 plot(1:109, rnorm(109), ylab="",xlab="", type="l", 
      col="red",xaxt="n",yaxt="n", lwd=2)
 axis(4)
 mtext("std. deviation",side=4,line=3)
 legend("topright",col=c("blue", "red"), lwd=2,
        legend=c("signal","std dev"), cex=0.85, bty="n", xjust=1)

Solution

As pointed out in the comments restarting an R session and using

legend("topright",col=c("blue", "red"), lwd=2,
 legend=c("signal","std dev"), cex=0.85, bty="n", xjust=1, seg.len=0.5)

solved my problems.

Comments

[Carl Witthoft]

It is often true that legends and text will show up in the "wrong" place if you change the plot window size after plotting. Best to set the window size first if you want a specific aspect ratio. E.g. dev.new(width=3,height=9)