From: Olaf Lenz (olenz_at_icp.uni-stuttgart.de)
Date: Tue May 22 2012 - 02:42:45 CDT

Hi!

Use the command "pcb box", and you'll get an automatically updating box.
About the "stretching", the command "pbc unwrap" might work for you.

Olaf

-- 
Dr. rer. nat. Olaf Lenz
Institut für Computerphysik, Pfaffenwaldring 27, D-70569 Stuttgart
Phone: +49-711-685-63607