解方程的二分法 matlab 程序

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解方程的二分法  matlab 程序  （ x^3-3*x^2+6*x-1=0）

% Bisection.m
% @# F$ w* @4 U+ Q: u+ w- p3 i. U) qfunction[k,x,f_value]=Bisection(f,a,b,eps1,eps2,N)
fprintf('k ,a ,b ,x, f\n')
for k=1:N
    x=(a+b)/2;
2 d' C8 m' W! N9 z2 L& D    f_value=f(x);
3 m7 |+ K* ^* @  @/ x+ t7 Y) B    fprintf( '%3d, %10.9f, %10.9f, %10.9f,%10.9f,\n'...
      ,k ,a ,b ,x, f_value)
0 j* ?+ V, c7 u+ Z* i! x3 s1 h    if abs(f_value)< eps1||0.5*(b-a)<eps2
    return
    else
        if f(x)*f(a)<0
( B# B) e; \& |% v) Y) @          b=x;
6 B  s5 Z3 I8 ]7 O2 ?        else
          a=x;
$ Y5 _2 x; m' \7 l        end
        if k== N
          warning ('算法超出最大迭代数!')   
        end
    end
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) J0 o" Q+ T* F+ B5 a; ^, J% examlpe7.m
a=0; b=1;
+ [/ V0 |- T( _% }/ a# Ueps1=1e-4;eps2=1e-4;
N=300;
$ R" P2 t8 ]5 s: q& hf=@ (x) (x^3-3*x^2+6*x-1);
- j- B6 l5 q$ {  E# Q9 h1 ]Hfun=@Bisection;
[k,x,f_value]= feval(Hfun, f,a,b,eps1,eps2,N);

运行结果
- K  c8 u4 C  h' K% x4 \# s; D% F>> examlpe7
k ,a ,b ,x, f
  1, 0.000000000, 1.000000000, 0.500000000,1.375000000,
* Q, I0 Q" T  q& r: c  2, 0.000000000, 0.500000000, 0.250000000,0.328125000,
0 S7 T) d3 U2 {, T8 o7 W: z  3, 0.000000000, 0.250000000, 0.125000000,-0.294921875,
  4, 0.125000000, 0.250000000, 0.187500000,0.026123047,
  5, 0.125000000, 0.187500000, 0.156250000,-0.131927490,
  6, 0.156250000, 0.187500000, 0.171875000,-0.052295685,
( C0 O- ^- |% i% u* g2 ?  7, 0.171875000, 0.187500000, 0.179687500,-0.012936115,
  8, 0.179687500, 0.187500000, 0.183593750,0.006630838,
  9, 0.179687500, 0.183593750, 0.181640625,-0.003143273,
% O: D% B5 X) U9 {' Z 10, 0.181640625, 0.183593750, 0.182617188,0.001746121,
11, 0.181640625, 0.182617188, 0.182128906,-0.000697991,
12, 0.182128906, 0.182617188, 0.182373047,0.000524211,
+ K5 b$ _0 u& R. a6 o) `; J 13, 0.182128906, 0.182373047, 0.182250977,-0.000086854,

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