[R] 'par mfrow' and not filling horizontally

[(Ted Harding)]

Greetings, Folks.
I'd appreciate being shown the way out of this one!
I've been round the documentation in ever-drecreasing
circles, and along other paths, without stumbling on
the answer.

The background to the question can be exemplified by
the example (no graphics window open to start with):

  set.seed(54321)
  X0 <- rnorm(50) ; Y0 <- rnorm(50)

  par(mfrow=c(2,1),mfg=c(1,1),cex=0.5)
  plot(X0,Y0,pch="+",col="blue",xlim=c(-3,3),ylim=c(-3,3),
  xlab="X",ylab="Y",main="My Plot",asp=1)

  par(mfg=c(2,1))
  plot(X0,Y0,pch="+",col="blue",xlim=c(-3,3),ylim=c(-3,3),
  xlab="X",ylab="Y",main="My Plot",asp=1)

As you will see, both plots have been extended laterally
to fill the plotting area horizontally, hence extend from
approx X = -8 to approx X = +8 (on my X11 display), despite
the xlim=c(-3,3); however, the "ylim=c(-3,3)" has been
respected, as has "asp=1".

What I would like to see, independently of the shape of
the graphics window, is a pair of square plots, each with
X and Y ranging from -3 to 3, even if this leaves empty
space in the graphics window on either side.

Hints?

With thanks,
Ted.

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E-Mail: (Ted Harding) <Ted.Harding at manchester.ac.uk>
Fax-to-email: +44 (0)870 094 0861
Date: 08-Sep-10                                       Time: 20:01:19
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