[R] Positioning plots on top of each other (aligment & borders)

[Jay]

Hello,

I want to place two plots on top of each other. However, the problem
is that I can't figure out a simple way to align them correctly. Is
there a way to specify this?
Since the data is bunch of coordinates and the second layer is an
outline of a map (a .ps file I import using the grImport package), I
suppose one option would be to specify a set of "artificial"
coordinates that make up the very corners of that plot, and then have
the second layer will this same space. Any ideas how to do this?


//John