%Script file to show the dynamics of points under x^2+c for
%  differing values of c=-2 and one choice below that

echo on

%
% Set 1:  These graphs are for c=-2
%
%The fixed points are pplus and pneg below:
c=-2;
f=inline('x.^2-2');
pplus=(1/2)*(1+sqrt(1-4*c));
pneg=(1/2)*(1-sqrt(1-4*c));


%Choose points in the intervals: >pplus, between -pplus and +pplus
% and less than -p+:
x=linspace(-pplus,pplus,30);
s=length(x);
for j=1:s
    figure(1)
    y=cobweb2(f,x(j),50,-2.5,2.5,-2.5,2.5);
    figure(2)
    plot(y)
    axis([0 50 -2 2])
    pause
    figure(1)
    clf
end

%
% Set 1:  These graphs are for c<-2
%
%The fixed points are pplus and pneg below:
c=-2.1;
f=inline('x.^2-2.1');
pplus=(1/2)*(1+sqrt(1-4*c));
pneg=(1/2)*(1-sqrt(1-4*c));


%Choose points in the intervals: >pplus, between -pplus and +pplus
% and less than -p+:
x=linspace(-pplus,pplus,20);
s=length(x);
for j=1:s
    figure(1)
    y=cobweb2(f,x(j),50,-2.5,2.5,-2.5,2.5);
    figure(2)
    plot(y(1:40))
    axis([1 40 -2 3]);
    pause
    figure(1)
    clf
end

echo off