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
function[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;
  W( m- e% q2 F$ x5 r- I% q- k    f_value=f(x);
) l0 w8 f5 {$ [5 _2 t: d9 g3 }# J- E    fprintf( '%3d, %10.9f, %10.9f, %10.9f,%10.9f,\n'...
* I! J) F4 ?( D      ,k ,a ,b ,x, f_value)
) L" t; v( P  B1 ~    if abs(f_value)< eps1||0.5*(b-a)<eps2
    return
. k; x. A! f( O" v    else
5 B: Q9 E/ E' R$ q* `: ^        if f(x)*f(a)<0
- l1 l* L, _' p) K8 Q, D' U2 ], U          b=x;
        else
/ h; X& D$ t& n; Q1 G) I7 o          a=x;
        end
        if k== N
          warning ('算法超出最大迭代數(shù)!')   
        end
: f% g6 E$ n# E; Z1 E, k    end

% examlpe7.m
a=0; b=1;
8 S/ B& k0 f4 @! Peps1=1e-4;eps2=1e-4;
+ r/ ~7 d& C9 u6 J0 q- b% ` N=300;
( ]! p  \& i9 S4 q- b4 ^! K" sf=@ (x) (x^3-3*x^2+6*x-1);
4 e8 J% M4 Y, E8 j9 |! H& dHfun=@Bisection;
[k,x,f_value]= feval(Hfun, f,a,b,eps1,eps2,N);
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運行結(jié)果
- J. S) Y; [+ N( _, H>> examlpe7
k ,a ,b ,x, f
  1, 0.000000000, 1.000000000, 0.500000000,1.375000000,
( @  C& P- h* S0 {: ?  2, 0.000000000, 0.500000000, 0.250000000,0.328125000,
1 P' a4 B$ O4 }! `% k" v: o  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,
2 n$ n3 W4 E# U  6, 0.156250000, 0.187500000, 0.171875000,-0.052295685,
  7, 0.171875000, 0.187500000, 0.179687500,-0.012936115,
6 x8 Q3 V8 Z; C  8, 0.179687500, 0.187500000, 0.183593750,0.006630838,
& |3 V  J/ B! j/ Q2 c1 Y  9, 0.179687500, 0.183593750, 0.181640625,-0.003143273,
10, 0.181640625, 0.183593750, 0.182617188,0.001746121,
' [' M; u% e6 B: K  a6 U2 m. X 11, 0.181640625, 0.182617188, 0.182128906,-0.000697991,
12, 0.182128906, 0.182617188, 0.182373047,0.000524211,
13, 0.182128906, 0.182373047, 0.182250977,-0.000086854,


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