²é¿´: 1649  |  »Ø¸´: 6
µ±Ç°Ö»ÏÔʾÂú×ãÖ¸¶¨Ìõ¼þµÄ»ØÌû£¬µã»÷ÕâÀï²é¿´±¾»°ÌâµÄËùÓлØÌû

wwÍôºì

гæ (СÓÐÃûÆø)

[ÇóÖú] Çó´óÉñ½âÊÍ~~F=@(p,x)p(1)*x(:,1).^2+p(2)*x(:,1).*x(:,2)+p(3)*x(:,2).^2+p(4); ÒÑÓÐ1È˲ÎÓë

F=@(p,x)p(1)*x(:,1).^2+p(2)*x(:,1).*x(:,2)+p(3)*x(:,2).^2+p(4);
% ÀëÉ¢Êý¾Ýµã
x=load('G:\Users\Daniel\Desktop\Total.txt');
p0=[1 1 1 1];
warning off
% ÄâºÏϵÊý,×îС¶þ³Ë·½·¨
p=nlinfit(x,zeros(size(x,1),1),F,p0);
plot(x(:,1),x(:,2),'r.');
axis square;
hold on;
xmin=min(x(:,1));
xmax=max(x(:,1));
ymin=min(x(:,2));
ymax=max(x(:,2));
% ×÷ͼ
ezplot(@(x,y)F(p,[x,y]),[-1+xmin,1+xmax,-1+ymin,1+ymax]);
title('ÇúÏßÄâºÏ');
legend('Ñù±¾µã','ÄâºÏÇúÏß')
set(gca,'xtick',[-1:0.2:1]);
set(gca,'ytick',[-1:0.2:1]);
xlim([-1 1]);
ylim([-1 1]);
line([-1 1],[0 0]);
line([0 0],[-1 1]);

Âé·³ÇëÎÊÄܲ»ÄÜÉèÖÃÄâºÏ³öÀ´µÄÍÖÔ²³¤ÖáÑØy·½Ïò£¬¶ÌÖáÑØx·½Ïò£¿
»¹ÓÐÕâ¸ö¹«Ê½F=@(p,x)p(1)*x(:,1).^2+p(2)*x(:,1).*x(:,2)+p(3)*x(:,2).^2+p(4)

Äĸö´ú±í³¤ÖáÄĸö´ú±í¶ÌÖáѽ~£¿Ð¡°×Ò»¸ö¹òл´óÉñ
»Ø¸´´ËÂ¥
ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû

wwÍôºì

гæ (СÓÐÃûÆø)

ÒýÓûØÌû:
3Â¥: Originally posted by guo_zy_123 at 2015-12-27 09:44:23
³¤¶ÌÖṫʽÎҾͲ»ÁÐÁ˰É

Õâ¸ö¸ßÖÐÉúµÄ¶«Î÷£¬×Ô¼º²éÒ»ÏÂÏÂ

x^2/(a^2)+y^2/(b^2) = 1

°ÑÇó½â³öµÄpת»»³ÉÉÏÃæµÄ±ê×¼¸ñʽ

ab¶¼ÄÜÇó£¬È»ºó±È½Ï´óС¾ÍÐÐÁË¡£¡£¡£¡£

pµÄ½âÔÚÄÄ¿ÉÒÔ¿´µ½£¿
Âé·³¾ÙÀý˵һÏ£¬ÔõôÑùÀûÓÃpÖµÇó½â ab
лл~£¡
6Â¥2015-12-27 15:28:29
ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû
²é¿´È«²¿ 7 ¸ö»Ø´ð

guo_zy_123

ľ³æ (ÕýʽдÊÖ)

¡¾´ð°¸¡¿Ó¦Öú»ØÌû

¸Ðл²ÎÓ룬ӦÖúÖ¸Êý +1
F=@(p,x)p(1)*x(:,1).^2+p(2)*x(:,2).^2+p(3)%ÄäÃûº¯Êýд³ÉÕâ¸ö

%PµÄ³õÖµÖ»Òª
p0 = [1 1 1];

ÆäËû²¿·Ö²»±ä

ÉϴθøÄã³ÌÐòÁË£¬³¤¶ÌÖᣬ¸ù¾ÝËã³öÀ´µÄ³¤¶ÌÖᣬ±È½Ï´óС¾ÍÐÐÁË

¼ûÄã×Ô¼ºÉÏÒ»¸öÌû×Ó
ÀϹŶ­
2Â¥2015-12-27 09:42:02
ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû

guo_zy_123

ľ³æ (ÕýʽдÊÖ)

¡¾´ð°¸¡¿Ó¦Öú»ØÌû

³¤¶ÌÖṫʽÎҾͲ»ÁÐÁ˰É

Õâ¸ö¸ßÖÐÉúµÄ¶«Î÷£¬×Ô¼º²éÒ»ÏÂÏÂ

x^2/(a^2)+y^2/(b^2) = 1

°ÑÇó½â³öµÄpת»»³ÉÉÏÃæµÄ±ê×¼¸ñʽ

ab¶¼ÄÜÇó£¬È»ºó±È½Ï´óС¾ÍÐÐÁË¡£¡£¡£¡£
ÀϹŶ­
3Â¥2015-12-27 09:44:23
ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû

guo_zy_123

ľ³æ (ÕýʽдÊÖ)

¡¾´ð°¸¡¿Ó¦Öú»ØÌû

Õâ´Î¿´ÁËÄãµÄÊý¾Ý£¬
ÒÔǰûÓп´¹ý

¸Ð¾õÄãµÄÊý¾Ý±È½ÏÊʺϷֶÎÄâºÏ

±È½ÏÃ÷ÏÔµÄÊǼ¸¸ö»·×´Êý¾Ý

ÂÌÉ«µÄÏßÊÇËùÓÐÊý¾ÝÓÃ×îС¶þ³Ë·¨ÄâºÏµÄ£¬

À¶É«µÄÏßÊÇ·ÖÁ˼¸¸ö¶ÎÄâºÏµÄ

À¶É«ÄâºÏµÄ»ù´¡ÊÇÊý¾Ý¸ù¾Ýµ½Ô­µãµÄ¾ßÌå°ÑÊý¾ÝÊÖ¶¯·Ö¼¸À࣬Ȼºó¾ÍÄÜ×öÁË
Çó´óÉñ½âÊÍ~~F=@(p,x)p(1)*x(:,1).^2+p(2)*x(:,1).*x(:,2)+p(3)*x(:,2).^2+p(4);
·Ö¶ÎÄâºÏ.jpg

ÀϹŶ­
4Â¥2015-12-27 09:58:20
ÒÑÔÄ   »Ø¸´´ËÂ¥   ¹Ø×¢TA ¸øTA·¢ÏûÏ¢ ËÍTAºì»¨ TAµÄ»ØÌû
×î¾ßÈËÆøÈÈÌûÍÆ¼ö [²é¿´È«²¿] ×÷Õß »Ø/¿´ ×îºó·¢±í
[¿¼ÑÐ] 304Çóµ÷¼Á +6 ÂüÊâ2266 2026-03-18 6/300 2026-03-21 00:32 by JourneyLucky
[¿¼ÑÐ] Ò»Ö¾Ô¸Äϲý´óѧ£¬327·Ö£¬²ÄÁÏÓ뻯¹¤085600 +9 Ncdx123456 2026-03-19 9/450 2026-03-20 23:41 by lovewei0727
[¿¼ÑÐ] 317Çóµ÷¼Á +5 Éê×ÓÉêÉê 2026-03-19 9/450 2026-03-20 22:26 by JourneyLucky
[¿¼ÑÐ] 290Çóµ÷¼Á +7 ^O^Ø¿ 2026-03-19 7/350 2026-03-20 21:43 by JourneyLucky
[¿¼ÑÐ] Çóµ÷¼ÁÒ»Ö¾Ô¸ÄϾ©º½¿Õº½Ìì´óѧ289·Ö +3 @taotao 2026-03-19 3/150 2026-03-20 21:34 by JourneyLucky
[¿¼ÑÐ] Ò»Ö¾Ô¸Î÷ÄϽ»Í¨ ר˶ ²ÄÁÏ355 ±¾¿ÆË«·Ç Çóµ÷¼Á +5 Î÷ÄϽ»Í¨×¨²Ä355 2026-03-19 5/250 2026-03-20 21:10 by JourneyLucky
[¿¼ÑÐ] 265Çóµ÷¼Á +12 ÁºÁºÐ£Ð£ 2026-03-19 13/650 2026-03-20 21:01 by Î޼ʵIJÝÔ­
[¿¼ÑÐ] 261ÇóBÇøµ÷¼Á£¬¿ÆÑо­Àú·á¸» +3 Å£Ä̺Üæ 2026-03-20 4/200 2026-03-20 19:34 by JourneyLucky
[¿¼ÑÐ] Ò»Ö¾Ô¸ÄÏÀí¹¤085701»·¾³302Çóµ÷¼ÁԺУ +3 ¿ûè÷ÎÀ¶Ó 2026-03-20 3/150 2026-03-20 19:28 by zhukairuo
[¿¼ÑÐ] 271²ÄÁϹ¤³ÌÇóµ÷¼Á +7 .6lL 2026-03-18 7/350 2026-03-20 09:10 by xingguangj
[¿¼ÑÐ] ²ÄÁÏѧ˶318Çóµ÷¼Á +5 February_Feb 2026-03-19 5/250 2026-03-19 23:51 by 23Postgrad
[¿¼²©] É격26Äê +3 °Ë6°Ë68 2026-03-19 3/150 2026-03-19 19:43 by nxgogo
[¿¼ÑÐ] ²ÄÁÏ¿¼Ñе÷¼Á +3 xwt¡£ 2026-03-19 3/150 2026-03-19 11:22 by wãåÑôw
[¿¼ÑÐ] 346Çóµ÷¼Á[0856] +3 WayneLim327 2026-03-16 6/300 2026-03-19 11:21 by WayneLim327
[¿¼ÑÐ] 311Çóµ÷¼Á +6 26ÑÐ0 2026-03-15 6/300 2026-03-18 14:43 by haxia
[¿¼ÑÐ] ÉúÎïѧ071000 329·ÖÇóµ÷¼Á +3 ÎÒ°®ÉúÎïÉúÎﰮΠ2026-03-17 3/150 2026-03-18 10:12 by macy2011
[¿¼ÑÐ] 278Çóµ÷¼Á +5 ÑÌ»ðÏÈÓÚ´º 2026-03-17 5/250 2026-03-18 08:43 by ÐÇ¿ÕÐÇÔÂ
[¿¼ÑÐ] ¶«ÄÏ´óѧ364Çóµ÷¼Á +5 JasonYuiui 2026-03-15 5/250 2026-03-16 21:28 by ľ¹Ï¸à
[¿¼ÑÐ] 277²ÄÁÏ¿ÆÑ§Ó빤³Ì080500Çóµ÷¼Á +3 ×ÔÓɼå±ý¹û×Ó 2026-03-16 3/150 2026-03-16 14:10 by ÔËÆøyunqi
[¿¼ÑÐ] 297Ò»Ö¾Ô¸ÉϽ»085600Çóµ÷¼Á +5 Ö¸¼â°ËǧÀï 2026-03-14 5/250 2026-03-14 17:26 by a²»Ò×
ÐÅÏ¢Ìáʾ
ÇëÌî´¦ÀíÒâ¼û