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）
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7 K$ g2 C# [' A1 n& }, Q% Bisection.m
) F' V& P2 S% [5 P3 l/ T/ C) Ifunction[k,x,f_value]=Bisection(f,a,b,eps1,eps2,N)
: x  T: V" N9 g5 w7 mfprintf('k ,a ,b ,x, f\n')
2 |% I: u* ^. v1 tfor k=1:N
    x=(a+b)/2;
  C! ~  \  p3 a    f_value=f(x);
3 G' L$ W: x) y2 E) R4 M    fprintf( '%3d, %10.9f, %10.9f, %10.9f,%10.9f,\n'...
      ,k ,a ,b ,x, f_value)
    if abs(f_value)< eps1||0.5*(b-a)<eps2
) G1 T8 z3 N  q/ m' k# i! _    return
    else
        if f(x)*f(a)<0
          b=x;
# T/ o3 b) m! j# z; }. t5 f        else
9 }: e" \* v* w4 Q/ X( c2 X( P$ W          a=x;
        end
        if k== N
          warning ('算法超出最大迭代数!')   
8 Q9 m) U- m, c8 a" y, Q0 M        end
    end
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% examlpe7.m
' m! n  M. z- a9 V" y" w% |a=0; b=1;
eps1=1e-4;eps2=1e-4;
N=300;
; `" w2 _* n$ E& T8 q8 l% af=@ (x) (x^3-3*x^2+6*x-1);
. s6 H% w5 _4 ~- w) E; MHfun=@Bisection;
" O* A9 L8 \1 a7 R. U[k,x,f_value]= feval(Hfun, f,a,b,eps1,eps2,N);

运行结果
>> examlpe7
. k( A* i4 \! U8 A! H" Y4 M$ jk ,a ,b ,x, f
  1, 0.000000000, 1.000000000, 0.500000000,1.375000000,
+ o. `; I2 g% q% y* n5 T8 l  2, 0.000000000, 0.500000000, 0.250000000,0.328125000,
; b' C7 ?$ c3 @- j  }- \. Z& v  3, 0.000000000, 0.250000000, 0.125000000,-0.294921875,
; S, M- k+ E! L" z% J$ g  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,
( b8 W1 V( D  q. r0 L- ?. t  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,
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,
! B+ R; L( R5 s; X$ P. t 13, 0.182128906, 0.182373047, 0.182250977,-0.000086854,
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