NAME

       predprey - integrate the Lotka-Volterra system

SYNOPSIS

       predprey -help
         or
       predprey
              [-seed integer] [-points integer] [-f0 double] [-s0
              double] [-a double] [-b  double]  [-c  double]  [-d
              double] [-dt double]

DESCRIPTION

       Integrates  the  two-species  Lotka-Volterra predator-prey
       system,

       dF/dt = F(a - bS), dS/dt = S(cF - d),

       according to the specified parameters.

OPTIONS

       -seed integer
              Seed for random parameters.

       -points integer
              Number of points to produce.

       -f0 double
              Initial fish population.

       -s0 double
              Initial shark population.

       -a double
              Fish growth rate.

       -b double
              Shark consumption rate.

       -c double
              Fish nutritional value.

       -d double
              Shark death rate.

       -dt double
              Time step increment.

MISCELLANY

       The program uses a second-order Euler's method to  perform
       the  numerical integration, which is sufficient for simple
       tasks such as this.

BUGS

       No sanity checks are performed to make sure  that  any  of

       the options make sense.

AUTHOR

       Copyright (c) 1997, Gary William Flake.

       Permission  granted  for any use according to the standard
       GNU ``copyleft'' agreement provided that the author's com-
       ments  are  neither  modified nor removed.  No warranty is
       given or implied.