volutil is a package containing miscellaneous utilities to complement the feature of VMD, to facilitate the manipulation and analysis of 3D volumetric data. volutil contains two components.

  1. volutil command-line utility (C++ source code)

    volutil is a command-line utility for manipulating and analyzing .DX formatted volumetric maps such as those output by VMD's volmap command. volutil allows you to combine, average, add, smooth maps, etc. Furthermore, it's architecture makes it extremely easy for anyone to customize and write their own analysis or transformation routines without worrying about how to read/write/access the maps.

    volutil does not depend on external libraries and should be trivially compilable on any platform by simply typing make.

  2. pmfutils.tcl script

    The pmfutils.tcl utility script, along with an example script, provide a starting point for using the implicit ligand sampling analysis contained in VMD. Implicit ligand sampling allows one to compute and visualize the 3D potential of mean force (free energy) of placing a gas molecule anywhere inside a solvated macromolecule. This provides information regarding all the pathways and barriers for gas migration inside proteins.

Documentation is provided within the tarball.


If you have questions please send email to



UIUC Open Source License