function root=HalfInterval(f,a,b,eps)if(nargin==3) eps=1.0e-4;endf1=subs(sym(f),findsym(sym(f)),a);f2=subs(sym(f),findsym(sym(f)),b);if(f1==0) root=a;endif(f2==0) root=b;endif(f1*f2>0) disp('两端点函数值乘积大于0!'); return;else root=FindRoots(f,a,b,eps);endfunction r=FindRoots(f,a,b,eps)f_1=subs(sym(f),findsym(sym(f)),a);f_2=subs(sym(f),findsym(sym(f)),b);mf=subs(sym(f),findsym(sym(f)),(a+b)/2);if(f_1*mf>0) t=(a+b)/2; r=FindRoots(f,t,b,eps);else if(f_1*mf==0) r=(a+b)/2; else if(abs(b-a)<=eps) r=(b+3*a)/4; else s=(a+b)/2; r=FindRoots(f,a,s,eps); end endend这个程序是二分法的，
|
