bifish - shows a bifurcation diagram in a fish population discrete time model
The dynamical system fish is the following :
y=b*exp(-0.1*(x(k)_1+x(k)_2)); x(k+1)=[ y 2*y ; s 0.0]*x(k);
and the parameters s evolves to show the bifurcation diagram. fishr and fishr2 are constructed as above but with added white noises.
fishr y=b*exp(-0.1*(xk(1)+xk(2))) xkp1=[ y 2*y ; s*(1+0.1*(rand()-0.5)) 0.0]*xk fishr2 z=exp(-0.1*(xk(1)+xk(2))) xkp1=[ b*z**(1+0.1*(rand()-0.5)) 2*b*z**(1+0.1*(rand()-0.5)) ; s 0.0]*xk
The three macros fish, fishr, fishr2 are loaded in Scilab when calling bifish.