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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% Bisection.m
+ i7 @+ j8 s9 wfunction[k,x,f_value]=Bisection(f,a,b,eps1,eps2,N)
( `$ q1 W5 Y4 B" u1 H( sfprintf('k ,a ,b ,x, f\n')
for k=1:N
2 v/ o- E7 X1 |0 ^7 M1 g% B' s    x=(a+b)/2;
    f_value=f(x);
    fprintf( '%3d, %10.9f, %10.9f, %10.9f,%10.9f,\n'...
) C+ N! V+ x1 f" ^0 @5 `      ,k ,a ,b ,x, f_value)
! D/ v# K9 W* Q0 L7 r    if abs(f_value)< eps1||0.5*(b-a)<eps2
! ]4 j" L4 |4 L/ Z* }  A    return
' l- |8 N8 {. w# _! i' n1 Y7 v/ q    else
+ X8 Q$ a7 H! z, X$ i& m6 n* N        if f(x)*f(a)<0
          b=x;
        else
# w3 X; ?5 m  B& Y0 J          a=x;
" A$ e8 ~- s. C7 e1 z# ?$ H- i& l        end
        if k== N
' K9 `! i. s8 L          warning ('算法超出最大迭代数!')   
        end
    end
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' ^4 i$ H* }) r4 A- x( c; j% examlpe7.m
a=0; b=1;
" _. B8 x7 M5 t, beps1=1e-4;eps2=1e-4;
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8 J( O! m) }9 m& a, O" u& Vf=@ (x) (x^3-3*x^2+6*x-1);
Hfun=@Bisection;
[k,x,f_value]= feval(Hfun, f,a,b,eps1,eps2,N);

运行结果
>> examlpe7
k ,a ,b ,x, f
  1, 0.000000000, 1.000000000, 0.500000000,1.375000000,
& u' c& l+ j. Z. H- X5 k5 C  2, 0.000000000, 0.500000000, 0.250000000,0.328125000,
  3, 0.000000000, 0.250000000, 0.125000000,-0.294921875,
  4, 0.125000000, 0.250000000, 0.187500000,0.026123047,
4 G' e1 h8 g. B1 u$ y  5, 0.125000000, 0.187500000, 0.156250000,-0.131927490,
6 l/ Z8 }( k9 |0 p$ q& i  6, 0.156250000, 0.187500000, 0.171875000,-0.052295685,
0 ?& X: l: O: H. L" `% m  7, 0.171875000, 0.187500000, 0.179687500,-0.012936115,
  o7 m5 w3 p( ^( v9 k0 P  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,
, w. O% A: ?8 Y1 S# S+ m0 N. B" {( Y; ] 13, 0.182128906, 0.182373047, 0.182250977,-0.000086854,
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