[R] contour help

[Alexander Nervedi]

Hi

I'd like to draw some level plots but I just cant for the live of me figure 
out how to control the axis here.  The axis for both the contour plots below 
appear to be the same, although one is a subset of the other. I was 
wondering how I could explicitly specify the xand y axis locations here.

al

dat<-matrix(runif(50)*20, ncol = 5)
contour(dat)
contour(dat[1:2, 1:2])