From: Mary Karpen (
Date: Tue Feb 12 2008 - 07:34:42 CST

Does anyone know what the "GradientMag", the "Min Length", and the
"Max Length" sliders do in the APBS plugin for VMD 1.8.6? We have
plotted our field lines from an apbs pot.dx file, and would like to
compare the fields of a mutant protein to the wildtype. I assume the
"gradientmag" has something to do with the magnitude of the electric
field in a region, but gradientmag is not a simple cutoff, because we
find a maximum of lines somewhere in the midrange of the slider.


Mary Karpen, Ph.D.
Associate Professor
Chemistry Department
Grand Valley State University
Allendale, Michigan 49401
(616) 331-3778