atkenstablepoint.m

来自「《精通MATLAB科学计算》一书的实例源代码」· M 代码 · 共 24 行

function [root,n]=AtkenStablePoint(f,x0,eps)
if(nargin==2)
    eps=1.0e-4;
end

tol=1;
root=x0;
x(1:2)=0;
n=0;
m=0;
a2=x0;
while(tol>eps)
    n=n+1; 
    a1=a2;
    r1=root;
    root=subs(sym(f),findsym(sym(f)),r1)+r1;
    x(n)=root;
    if(n>2)
        m=m+1;
        a2=x(m)-(x(m+1)-x(m))^2/(x(m+2)-2*x(m+1)+x(m));
        tol=abs(a2-a1);
    end   
end
root=a2;