resetting the size of the workspace

[D M German <dmg uvic ca>]

Sometimes when I connect my laptop to an external display, the workspace
size grows to accommodate the sum of the two displays (think
cinerama). This is fine, except that then I like to reset the position
of the screens to overlap each other*. At that point I have all this
space to the right that I no longer need.  I want to resize the
workspace to the size of the largest display. Is there a way to this via
a command?

Thanks in advance,

* I use xrandr to reset the position of the screens to be offset
  0x0.  This effectively is like mirroring, but each screen keeps its
  native resolution, but the smaller screen does not show the area
  beyond its boundaries. That is ok, because in this situation I am
  using the larger screen only (display attached to my laptop).


xrandr --output VGA1 --mode 1024x768 --right-of LVDS1 --pos 1400x0 --output LVDS1 --mode 1400x1050 --pos 0x0 


-- 
--
Daniel M. German                  
http://turingmachine.org/
http://silvernegative.com/
dmg (at) uvic (dot) ca
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