优化设计黄金分割发以及迭代法

1、机械优化设计课程论文院 系机械工程系专业机械设计班级二班姓 名学 号一、优化题目应用所学计算机语言编写一维搜索的优化计算程序，完成计算结果和输出二、建立优化数学模型1、目标函数方程式：y=pow(x,4)-1*pow(x,3) -3*pow(x,2) -16*x+102、变量：x3、初始值：初始值 x1=5 初始步长 tt=0.01三、所选用的优化方法1、采用外推法确定搜索区间2、采用黄金分割法求函数最优3、计算框图：(1) 、外推法程序框图(2) 、黄金分割法程序框图黄金分割法计算框图四、计算输出内容:鈕 C:riIHDVSlezt 1=2=9.9£?5,1)=4.90001-1.

2、27392-2/6 5 J1 ti=3,a=l. 273?, b=4_9000,xl =2.6686,x2=l. 5148 Ffl=-22_S746FF2 =25.8993 Si2735=3-5148. xi-2.1299Px2=S.6536 Ji2fi.77ft5J3-22.5745 "5,&"1.2?3?=2.6586,«1=1.86202=2.12?9£12J-8?18pf2-26-?05 Si=6,a=1.8ft28,b=2-&5«6.xl=2.1299.k2=Z.3317.fl=-26-77a5.f2=-26-7356

3、 n=7,al. 802ft, b=2 _331?,xl =2. BS49 x2t, t3T9,f 126.016 ；f 226. ?705 ti =9,a=2.9W,S=2.3317, X1-2.1299.x2=i.20S9,fi=-2S.7»5,f 226.94)2 n =9,a-2,129b-2*3317Pxl =2.20£9rx2-!.!546ffl26.r4T2f f 226.?447 n-18,*-2-12?.b=2.254&,xl=2.1776.x2-2.206?,fl=-26.9074,f2=-26.?4?2 ji=lka-2-i7?G,h-2.25

4、4t,Kl=2.20G9,z2=2.2252 J1=-2G.9492 J2=-26.95ft4 n=i2rA-a.2 0£9rlj-2.254tfXi=2.22G9rx2=2.2 3&4,fl=-2£.95&4,P2=2G.73 n-13,A-2.206?Pb=2.2364,Kl-2.2181,K2-2.2252,fl=-26.9564,f2=-26.?5&4 <114,i=Z-2181,b=2.2364, xl =2.2252,x2=2.2294,fl=-2fi.?584,f2 =-26.9586 =15,a=2.2252,b=2.2364,

5、xi=2.2294,x2=2.2321Jl26.958&,f2-2G.9599 n=l£=a-22E2,b=5.232L,xl=2.257fl,K2=5.2254,ri=-SG.Kft6,f2=-aC.?Cftt n=17=2.2252,b=2.2294,jcl=2.226G.K2=2.2278,fl=-26.?585,f2=-26.9596 fi=ia,a=J-!26B,b=2.2294,xl=2.2278,x2=2.2234,fl=-J6.?5fl6,f2=-26.95ft6 n=19,a=2-2270rb=2.2294,zl=2.2294,x2=2.220a,fl=-2

6、G.958t,f2=-2G.Ka£ ti=20,=2.2278Pb-2.2288,Kl=2-2282,x2=2-2284,fl-!6.958fc,£2=-!6.K88 <i=21,A=2.2 28Z,b=2.228B,Kl=2.2284,K2=2.2286,fl=-26.?S86,f2=-26.?586 r=22=i.2282 Rb=2.228&,Kl=2.2283,x2=2.2284,fl=-26586 ,f2=-26.J5a6 n=22,a=a.2282,h=2-2284,l=2.229a,w2=2.2283,fl=-2G.?58&,F2=-2G-

7、flE&& n=24,i=2.2282,h=2_2281,xl=2.2S83,x2=2.2283,fl=-2G.7S8firf2=-26,95&6 ii=25pa=2.2 293Pb=2.2283,Kl=2l22832=2l2283,fl=-26l?58&pf2=-26B?59& Ilie min is 2.2283 and tlie result is 26.758fc_五、优化的源程序文件:#in clude<math.h>#i nclude<stdio.h>#defi neeO.OOOl#definett 0.01float

8、 f (doublex)float y=pow(x,4)-1*pow(x,3)-3*pow(x,2)-16*x+10; return(y);void fin di ng(float*p1,float*p2)float x1=10,x2,x3,t,f1,f2,f3,h=tt;int n=0;x2=x1+h;f仁f(x1);f2=f(x2);if(f2>f1)h=-h;x3=x1;f3=f1;x1=x2;f 仁f2;x3=x2+h;f3=f(x3);n=n+1;printf("n=%d,c1=%6.4lf,x2=%6.4lf,x3=%6.4lf,f1=%6.4lf,f2"

9、6.4lf,f3=%6.4lfn" ,n, x1,x2,x3,f1,f2,f3);while(f3<f2)h=2*h;x1=x2;f1=f2;x2=x3;f2=f3;x3=x2+h;f3=f(x3);n=n+1;printf("n=%d,x1=%6.4lf,x2=%6.4lf,x3=%6.4lf,f1=%6.4lf,f2=6.4%lf,f3=%6.4lfn",n,x 1,x2,x3,f1,f2,f3);if(h<0)t=x1;x1=x3;x3=t;*p1=x1;*p2=x3;main()floata,b,x1,x2,f1,f2,xmin,ymin,c;

10、int n=0;finding(&a,&b) ;printf("the areis%6.4lf to %6.4lfn",a,b); x1=b-0.618*(b-a);x2=a+0.618*(b-a);f1=f(x1);f2=f(x2);doif(f1>f2)a=x1;x1=x2;f1=f2;x2=a+0.618*(b -a);f2=f(x2);elseb=x2;x2=x1;f2=f1;x1=b -0.618*(b-a);f1=f(x1); n=n+1;printf("n=%d,a=%6.4lf,b=%6.4lf,x1=%6.4lf,x2=%6.4lf,f1=%6.4lf,f2=%6.4lfn",n,a,b ,x1,x2,f1,f2);c=fabs(b-a);while(c>e);xmin=(x1+x2