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
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;
    f_value=f(x);
    fprintf( '%3d, %10.9f, %10.9f, %10.9f,%10.9f,\n'...
      ,k ,a ,b ,x, f_value)
+ q: j3 D! b8 j! l7 G    if abs(f_value)< eps1||0.5*(b-a)<eps2
    return
0 g' L0 P+ @# \    else
6 f/ C9 @- l) a& c8 @        if f(x)*f(a)<0
% `, n4 ], C! G3 b          b=x;
, i& i9 D. o6 ]/ T' N        else
          a=x;
        end
        if k== N
+ ^8 @  S5 O' S: y5 |- S+ }          warning ('算法超出最大迭代數!')   
        end
/ e. M+ v" j- A2 ?+ h1 W7 y- m* Q    end
' c& }0 n1 u% d! g6 ^) V( ~# n8 f
% examlpe7.m
a=0; b=1;
eps1=1e-4;eps2=1e-4;
N=300;
f=@ (x) (x^3-3*x^2+6*x-1);
# k# X1 M/ ?; YHfun=@Bisection;
1 e1 r: p" g6 o  |% B# D5 o[k,x,f_value]= feval(Hfun, f,a,b,eps1,eps2,N);
# q" V" b: H. [
運行結果
. a* g3 o4 u& f. M9 |; }>> examlpe7
; ~+ L8 O: h" Y1 p! Rk ,a ,b ,x, f
  1, 0.000000000, 1.000000000, 0.500000000,1.375000000,
# Y* q$ x2 I' N& U/ _: h. _# A  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,
: v8 m$ I8 F; Q+ ?; ~/ Q. Y  5, 0.125000000, 0.187500000, 0.156250000,-0.131927490,
  6, 0.156250000, 0.187500000, 0.171875000,-0.052295685,
  7, 0.171875000, 0.187500000, 0.179687500,-0.012936115,
  8, 0.179687500, 0.187500000, 0.183593750,0.006630838,
8 Z' ^" m# G6 `  9, 0.179687500, 0.183593750, 0.181640625,-0.003143273,
2 \! b8 Q8 K( h4 M+ x 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,
  M) O  V$ \  z2 S" Z) ]1 b 13, 0.182128906, 0.182373047, 0.182250977,-0.000086854,