4Â¥: Originally posted by pdl9527 at 2017-01-10 22:05:11
ËùÒÔÎÊÌâµÄ¹Ø¼üÊÇÈçºÎ¶ÁÈ¡excelÖеÄÊý¾ÝÈ»ºó¸³Öµ¸øx,y,u,v¡£
ÓÉÓÚ²»ÖªµÀÄãµÄexcelÎļþµÄ¾ßÌå¸ñʽ£¬ÎÒ¸ù¾ÝÄãµÄͼƬ×öÁËÒ»¸öexcel²¢ÇÒ±àдÁËÏàÓ¦µÄÊý¾ÝÌáÈ¡ºÍ¼ÆËã³ÌÐò£¬Ï£Íû¶ÔÄãÓÐÆô·¢¡£


function question_19 ...

a=[4 -1 1;-18 3 -1; 1 1 1];
b=[5 -15 6]';
x=a\b

2Â¥: Originally posted by pdl9527 at 2017-01-09 21:11:02
Ö»ÓÐ8¸öδ֪Êýµ«ÊÇÈ´ÓÐ16¸ö·½³Ì£¿
ÕâÖÖ½âÏßÐÔ·½³Ì×éµÄÎÊÌâÓÃ×ó³ý¾Í¿ÉÒԸ㶨ÁË£¬¾Ù¸öÀý×Ó¡£
4x1-x2+x3=5;
-18x1+3x2-x3=-15;
x1+x2+x3=6;£»
Çóx1 x2 x3

a=;
b=';
x=a\b
...

3Â¥: Originally posted by С¹íľľ at 2017-01-10 18:38:32
ллÄúµÄ½â´ð£¬¶øÎÒµÄÒâ˼ÊÇ£¬ÎÒ½ÓÏÂÀ´¿ÉÄÜ»áÓкܶàÕâÑùµÄÊý¾Ý£¬ÔõôÓÃMATLAB°Ñ±íÖÐÊý¾ÝÖ±½Ó´øÈë¾ØÕó·½³ÌÖУ¬¶ø²»ÊÇÓÃÊÖ¶¯ÊäÈ룿...

function question_19
%2017-1-10
clear;clc
%×¢ÒâÐ޸ķ¾¶
[~,text,~]=xlsread('X:\My Desktop\data.xlsx');
count=1;
for k=1:size(text,1)
    num=text{k,1};
    if isempty(num) || isempty(str2num(num(2:strfind(num,',')-1)))
        continue;
    end
    for i=1:size(text,2)
        num=text{k,i};
        div=strfind(num,',');
        a(count,i)=str2num(num(2:div-1));
        b(count,i)=str2num(num(div+1:end-1));
    end
    count=count+1;
end
%ÒÔÉϳÌÐòÓÃÀ´ÌáÈ¡Êý¾Ý£¬ÒÔϳÌÐòÓÃÀ´¼ÆËã²ÎÊý
x=a(1,:);
y=b(1,:);
u=a(2,:);
v=b(2,:);
row1=[x' y' ones(8,1) zeros(8,3) -(x.*u)' -(y.*u)'];
row2=[zeros(8,3) x' y' ones(8,1) -(x.*v)' -(y.*v)'];
%ÓÉÓÚÖ»ÐèÒª8¸ö·½³Ì¾Í¿ÉÒÔÁË£¬ËùÒÔ´æÔÚ¶àÖÖ¼ÆËã²ÎÊýµÄ·½·¨¡£
x1=row1\u'
x2=row2\v'