黄金分割法机械优化设计C语言程序.doc

黄金分割法的优化设计实验报告学院:机电工程机制自动化11-03班学号:541102010326姓名:刘点点1,黄金分割法的程序流程图2,对应流程图的C语言程序下面应用C语言程序利用黄金分割法求一元函数F=x^2+2*x的最优解,已知初始区间为[-3,5],取收敛精度e=10-4。C语言程序如下:#include<>#include<>#definef(x)pow(x,2)+2*x#(){ doubley1,y2,x1,x2,x,a,b,e; intn;n=1;printf("请输入收敛精度e="); scanf("%lf",&e); printf("请输入区间左值a="); scanf("%lf",&a); printf("请输入区间右值b="); scanf("%lf",&b); printf("nabx1x2y1y2\n"); x1=b-M*(b-a);x2=a+M*(b-a);y1=f(x1);y2=f(x2);printf("%d%.4lf%.4lf%.4lf%.4lf%.4lf%.4lf\n",n,a,b,x1,x2,y1,y2);n=n++;do{if(y1<y2){b=x2;x2=x1;y2=y1;x1=b-M*(b-a);y1=f(x1);printf("%d%.4lf%.4lf%.4lf%.4lf%.4lf%.4lf\n",n,a,b,x1,x2,y1,y2);n=n++;}else{a=x1;x1=x2;y1=y2;x2=a+M*(b-a);y2=f(x2);printf("%d%.4lf%.4lf%.4lf%.4lf%.4lf%.4lf\n",n,a,b,x1,x2,y1,y2);n=n++;}}while(fabs((b-a)/b)>=e&&fabs((y2-y1)/y2)>=e); x=(a+b)*;printf("x=%.5lf\n",x);getchar();}:假定经十二次迭代后已满足收敛精度要求,则得x*=1/2(a+b)=1/2(--)=-,相应的函数极值f(x*)=-;