求牛顿-拉夫逊法matlab代码？

tianya7071

求牛顿-拉夫逊法matlab代码？
谢谢！

风花雪月

1. function [P,iter,err]=newdim(F,JF,P,delta,epsilon,max1)
   
2. %Input   -F is the system saved as the M-file F.m
   
3. %        -JF is the Jacobian of F saved as the M-file JF.m
   
4. %        -P is the initial approximation to the solution
   
5. %        -delta is the tolerance for P
   
6. %        -epsilon is the tolerance for F(P)
   
7. %        -max1 is the maximum number of iterations
   
8. % Output -P is the approximation to the solution
   
9. %        -iter is the number of iterations required
   
10. %        -err is the error estimate of P
    
11. Y=feval(F,P);
    
12. for k=1:max1
    
13.     J=feval(JF,P);
    
14.     Q=P-(J\Y')';
    
15.     Z=feval(F,Q);
    
16.     err=norm(Q-P);
    
17.     relerr=err/(norm(Q)+eps);
    
18.     P=Q;
    
19.     Y=Z;
    
20.     iter=k;
    
21.     if (err<delta)|(relerr<delta)|(abs(Y)<epsilon)
    
22.         break;
    
23.     end
    
24. end

复制代码

茹果刘儿

好东西~学习了~