bifish(1)

NAME
bifish - shows a bifurcation diagram in a fish population discrete time model

CALLING SEQUENCE
bifish([f_ch])

PARAMETERS

f_ch
    : can be one of fish, fishr and fishr2. This option selects the population model.

DESCRIPTION
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

SEE ALSO
ode