predprey.deq

defequ

unknown[0]:="x";
unknown[1]:="y";

x'(t):={ a*x(t-h1)-b*y*x-m*x*x };
y'(t):={ e*y(t-h2)+(c*x-d)*y-n*y*y };

a:=2;
b:=1;
m:=0.01;
h1:=0.1;
c:=0.5;
d:=1;
e:=0.5;
n:=0.01;
h2:=0.3;

x_(t):={3};
y_(t):={3};
     t0:=0.0;
maxt:=100;
     dt:=0.05;