XGAS(1)                     X Version 11(Release 5)                     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.

X DEFAULTS
      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)





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XGAS(1)                     X Version 11(Release 5)                     XGAS(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













































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