xgas(1)

     NAME
          xgas - animated simulation of an ideal gas

     SYNOPSIS
          xgas [-option ...]

     DESCRIPTION
          xgas is a physical simulation of an ideal gas in a heated
          box.  Gas molecules move around the box with velocities
          dependent on their temperature.  A chamber consisting of two
          boxes contains the gas molecules; the temperature of each
          box can be independently controlled by a scrollbar.  When
          gas molecules collide with the walls, their temperature
          approaches that of the box.

          Use mouse button 1 to create molecules one at a time at the
          cursor position.  Use mouse button 2 to create the maximum
          number of molecules at the cursor position.

     OPTIONS
          This is a toolkit program;
                  all the usual toolkit options are available.

          -ts     Sets the timeStepSize resource.

          -d      Sets the delay resource.

          -rb     Sets the randomBounce resource.

          -eq     Sets the equilibrium resource.

          -mm     Sets the maxMolecules resource.

          -fg     Sets the foreground.

          -bg     Sets the background.

     RESOURCES
          The xgas program uses the following X resources:

          timeStepSize
                  Specifies the simulated time duration in
                  microseconds for each cycle of computation.

          delay   Specifies the real time interval between timestep
                  computations.

          randomBounce
                  In each wall collision, a molecule bounces
                  elastically (angle of incidence = angle of
                  reflection).  A component of randomness is added to
                  this angle.  RandomBounce varies from 0.0 (no
                  randomness) to 1.0 (completely random angle of
                  incidence).

          equilibrium
                  During each wall collision, a molecule's kinetic
                  energy approaches that corresponding to the
                  temperature of the wall.  If equilibrium is 1.0, the
                  molecule reaches the wall temperature immediately.
                  For values between 1.0 and 0.0, the molecule
                  approaches the temperature of the wall more slowly.

          maxMolecules
                  Specifies the maximum number of molecules in the
                  simulation.

     SEE ALSO
          X(1), xwd(1)

     BUGS
          When the chamber is resized, molecules should be rearranged
          appropriately.  Instead, the molecule arrays are
          reinitialized.

     COPYRIGHT
          Copyright 1991, Massachusetts Institute of Technology.

     AUTHOR
          Larry Medwin