±±¾©Ê¯ÓÍ»¯¹¤Ñ§Ôº2026ÄêÑо¿ÉúÕÐÉú½ÓÊÕµ÷¼Á¹«¸æ
²é¿´: 1507  |  »Ø¸´: 3

xuetb

Ìú³æ (³õÈëÎÄ̳)

[ÇóÖú] matlab×îС¶þ³ËÎÊÌâÇóÖú Ôõô¶¨Òå¶à±äÁ¿

×îС¶þ³ËÎÊÌ⣺
·ÇÏßÐÔ×îС¶þ³ËÎÊÌ⣺minf^2 ÆäÖУ¬ f=[x1+10*x2;sqrt(5)*(x3-x4);(x2-2*x3)^2;sqrt(10)*(x1-x4)^2];x0=[3,-1,0,1]
³ÌÐòÈçÏ£¬¿ÉÒÔÇóµ¥±äÁ¿£¬Ôõô¶¨Òåx=[x1,x2,x3,x4],Çó½âÄØ£¿  Çë¸ßÊÖÖ¸½Ì                        
function fv = Funval( f,varec,varval )
%UNTITLED Summary of this function goes here
%   Detailed explanation goes here
tic;
var = findsym(f);
varc = findsym(varec);
s1=length(var);
s2=length(varc);
m=floor((s1-1)/3+1);
varv=zeros(1,m);
if s1~=s2
    for i=0(s1-1)/3)
        k=findstr(varc,var(3*i+1));
        index=(k-1)/3;
        varv(i+1)=varval(index+1);
    end
    fv=subs(f,var,varv);
else
    fv=subs(f,varec,varval);
end
end
x=[x1,x2,x3,x4];
function [x,minf]= minGN(f,x0,var,eps)%Ä¿±êº¯Êý;f;³õʼµã:x0£¬×Ô±äÁ¿ÏòÁ¿;var,
  %¾«¶È£ºeps£¬Ä¿±êº¯Êý×îСֵʱµÄxÒÔ¼°Ä¿±êº¯Êý×îСֵ
  format long;
  if nargin==4
      eps=1.0e-5;
  end
  S=transpose(f)*f;
  k=length(f);
  n=length(x0);
  x0=transpose(x0);
  tol=1;
  A=jacobian(f,var);
  while tol>eps
      Fx=zeros(k,1);
      for i=1:k
          Fx(i,1)=Funval(f(i),var,x0);
      end
      Sx=Funval(S,var,x0);
      Ax=Funval(A,var,x0);
      gSx=transpose(Ax)*Fx;
      dx=-transpose(Ax)*Fx;
      x0=x0+dx;
      tol=norm(dx);
  end
  x=x0;
  minf=Funval(S,var,x);
  format short;
  toc;
  Iterations;
end
»Ø¸´´ËÂ¥

» ²ÂÄãϲ»¶

» ±¾Ö÷ÌâÏà¹Ø¼ÛÖµÌùÍÆ¼ö£¬¶ÔÄúͬÑùÓаïÖú:

ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû

xuetb

Ìú³æ (³õÈëÎÄ̳)

²¹³ä£ºÅ¼ÔÚmatlabÖÐÊäÈ룺 syms x=[x1 x2 x3 x4];f=[x1+10*x2;sqrt(5)*(x3-x4);(x2-2*x3)^2;sqrt(10)*(x1-x4)^2];x0=[3,-1,0,1];[x,minf]=minGN(f,x0,[x],1.0e-5),S,A,k
´íÎó£º Error using ==> syms at 61
Not a valid variable name.
2Â¥2011-12-05 15:54:01
ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû

zhfzh

ľ³æ (ÕýʽдÊÖ)

¡¾´ð°¸¡¿Ó¦Öú»ØÌû

¡ï
ÓàÔó³É(½ð±Ò+1): лл²ÎÓëÓ¦Öú£¡»¶Ó­³£À´³ÌÐòÓïÑ԰棡 2011-12-08 14:06:03
Äã¿ÉÒÔÓÃstrcat¡¢  evalº¯Êýͨ¹ýÑ­»·À´ÊµÏÖ¶à¸ö±äÁ¿µÄ¶¨Òå
3Â¥2011-12-05 17:11:33
ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû

xuetb

Ìú³æ (³õÈëÎÄ̳)

ÒýÓûØÌû:
3Â¥: Originally posted by zhfzh at 2011-12-05 17:11:33:
Äã¿ÉÒÔÓÃstrcat¡¢  evalº¯Êýͨ¹ýÑ­»·À´ÊµÏÖ¶à¸ö±äÁ¿µÄ¶¨Òå

ÄܰïÖú±àдÏÂô£¿ ÈçºÎʵÏÖ£¿Ð»Ð»À²
4Â¥2011-12-06 00:54:46
ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû
Ïà¹Ø°æ¿éÌø×ª ÎÒÒª¶©ÔÄÂ¥Ö÷ xuetb µÄÖ÷Ìâ¸üÐÂ
×î¾ßÈËÆøÈÈÌûÍÆ¼ö [²é¿´È«²¿] ×÷Õß »Ø/¿´ ×îºó·¢±í
[¿¼ÑÐ] 085410È˹¤ÖÇÄÜ ³õÊÔ316·Ö Çóµ÷¼Á +7 ²ÐÐÇ·÷Êï 2026-03-31 7/350 2026-04-06 10:09 by À¶ÔÆË¼Óê
[¿¼ÑÐ] 262Çóµ÷¼Á +7 ÌìϵÚÒ»ÎÄ 2026-04-04 8/400 2026-04-05 21:31 by ¼¤Á÷Ó¶É
[¿¼ÑÐ] 086000ÉúÎïÓëÒ½Ò©298µ÷¼ÁÇóÖú +9 ÔªÔªÇàÇà 2026-03-31 12/600 2026-04-05 21:03 by ѧԱ8dgXkO
[¿¼ÑÐ] 283Çóµ÷¼Á +5 baiiyu 2026-04-05 6/300 2026-04-05 20:35 by à£à£à£0119
[¿¼ÑÐ] µ÷¼Á +5 ºÃºÃ¶ÁÊé¡£ 2026-04-01 5/250 2026-04-05 17:54 by liucky
[¿¼ÑÐ] ÊýÒ»Ó¢Ò» 347 È˹¤ÖÇÄܹú½±ÂÛÎͼÓÐÇóµ÷¼Á +3 ÎÚÀ­¶ùɽÂö 2026-03-30 7/350 2026-04-05 10:32 by zhq0425
[¿¼ÑÐ] 313Çóµ÷¼Á +3 º£ÈÕº£ÈÕ 2026-04-04 3/150 2026-04-05 07:48 by 544594351
[¿¼ÑÐ] Äܶ¯µ÷¼Á326ר˶ +4 wan112233 2026-04-04 4/200 2026-04-04 22:47 by yu221
[¿¼ÑÐ] 0854Çóµ÷¼Á +4 assdll 2026-04-03 4/200 2026-04-04 22:17 by hemengdong
[¿¼ÑÐ] 324Çóµ÷¼Á +14 ÏëÉÏѧÇóµ÷ 2026-04-02 15/750 2026-04-04 20:31 by Î޼ʵIJÝÔ­
[¿¼ÑÐ] 309·Ö085801Çóµ÷¼Á +11 MY_angel 2026-03-31 11/550 2026-04-04 19:11 by À¶ÔÆË¼Óê
[¿¼ÑÐ] 293·ÖÇóµ÷¼Á£¬ÍâÓïΪ¶íÓï +6 ¼ÓÒ»Ò»¾Å 2026-03-31 6/300 2026-04-04 14:57 by ´ÏÃ÷µÄ´óËÉÊó
[¿¼ÑÐ] һ־Ը˫·Ç085502£¬267·Ö£¬¹ýËļ¶Çóµ÷¼Á +3 ÔÙæҲҪ³Ô·¹°¡ 2026-04-03 3/150 2026-04-04 05:03 by gswylq
[¿¼ÑÐ] 320Çóµ÷¼Á +3 ũҵ¹¤³ÌÓëÐÅÏ¢¼ 2026-04-03 3/150 2026-04-03 11:40 by ÍÁľ˶ʿÕÐÉú
[¿¼ÑÐ] 260Çóµ÷¼Á +3 ÖìÜÆÁÕ 2026-04-02 3/150 2026-04-03 08:44 by yulian1987
[¿¼ÑÐ] ²ÄÁÏר˶322·Ö +11 ¹þ¹þ¹þºðºðºð¹þ 2026-04-01 11/550 2026-04-02 10:52 by lnilvy
[¿¼ÑÐ] 0710ÉúÎïѧ£¬325Çóµ÷¼Á +3 mkkkkkl 2026-04-01 3/150 2026-04-02 09:48 by Jaylen.
[¿¼ÑÐ] ʡ˫һÁ÷ÖØµãÒ»±¾´óѧÕÐÊÕµ÷¼Á +4 wwwwffffff 2026-03-31 7/350 2026-04-01 15:23 by wwwwffffff
[¿¼ÑÐ] ²ÄÁϵ÷¼Á +10 Eujd1 2026-03-31 11/550 2026-04-01 11:23 by ivanqyq
[¿¼ÑÐ] 085404 22408 315·Ö +5 zhuangyan123 2026-03-31 6/300 2026-03-31 13:48 by limeifeng
ÐÅÏ¢Ìáʾ
ÇëÌî´¦ÀíÒâ¼û