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）

) ~* K! T; x. j* v8 o5 I- I# I% Bisection.m
function[k,x,f_value]=Bisection(f,a,b,eps1,eps2,N)
fprintf('k ,a ,b ,x, f\n')
) ?" p3 A& {& I4 O4 U+ X3 ~for k=1:N
    x=(a+b)/2;
    f_value=f(x);
    fprintf( '%3d, %10.9f, %10.9f, %10.9f,%10.9f,\n'...
/ b# U8 W& g! y' d' ]7 k      ,k ,a ,b ,x, f_value)
    if abs(f_value)< eps1||0.5*(b-a)<eps2
6 r0 D( l$ d4 E" R' r    return
    else
% S( {! g+ J6 _9 a/ [        if f(x)*f(a)<0
% B6 x6 Z) e1 T7 I& z0 A          b=x;
) x4 x! M. E( z# Y        else
4 x9 w- D6 V) E/ i1 h          a=x;
        end
        if k== N
          warning ('算法超出最大迭代數!')   
        end
7 m0 d+ O& s) a2 L' y7 X- N; u    end
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! \( P, _/ Z( D. s% examlpe7.m
a=0; b=1;
eps1=1e-4;eps2=1e-4;
N=300;
f=@ (x) (x^3-3*x^2+6*x-1);
* ~3 m8 F+ K5 Z- }4 E6 B6 ?7 p# D' o% fHfun=@Bisection;
[k,x,f_value]= feval(Hfun, f,a,b,eps1,eps2,N);
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4 o' E# T( l, w& f  y8 F運行結果
>> examlpe7
$ q) j* I5 g4 h& @% Bk ,a ,b ,x, f
  1, 0.000000000, 1.000000000, 0.500000000,1.375000000,
$ ?* C, u1 H" H# n7 K  2, 0.000000000, 0.500000000, 0.250000000,0.328125000,
  3, 0.000000000, 0.250000000, 0.125000000,-0.294921875,
8 t. w+ [0 L2 v. y" B; \8 J  4, 0.125000000, 0.250000000, 0.187500000,0.026123047,
0 L7 ?* C1 Z* q  5, 0.125000000, 0.187500000, 0.156250000,-0.131927490,
( j7 i% A7 ]8 C: B5 b  6, 0.156250000, 0.187500000, 0.171875000,-0.052295685,
$ G2 `2 V( w& S5 \& `+ s- ]  7, 0.171875000, 0.187500000, 0.179687500,-0.012936115,
9 ^* ?8 F' u3 l) O( g4 T) ?  8, 0.179687500, 0.187500000, 0.183593750,0.006630838,
  9, 0.179687500, 0.183593750, 0.181640625,-0.003143273,
10, 0.181640625, 0.183593750, 0.182617188,0.001746121,
11, 0.181640625, 0.182617188, 0.182128906,-0.000697991,
( O, W6 k' {3 j# h 12, 0.182128906, 0.182617188, 0.182373047,0.000524211,
13, 0.182128906, 0.182373047, 0.182250977,-0.000086854,

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