how to compare a line a of matrix with another ?

2 次查看（过去 30 天）

显示更早的评论

Paul Nanfah 2015-6-17

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/224261-how-to-compare-a-line-a-of-matrix-with-another

编辑： dpb 2015-6-23

采纳的回答： dpb

在 MATLAB Online 中打开

hello, giving the following matrix :

matrix=[5 6 4;3 4 4;5 6 4;7 8 4;9 10 4;1 2 4];

I want to compare the first 2 elements of each rows and display a message if 2(or more) of them have the same elements

I tried to do it this way:

matrix=[5 6 4;3 4 4;5 6 4;7 8 4;9 10 4;1 2 4];
for i=1:size(matrix,1)
      a=matrix(i,1);
        for k=1:size(matrix,2)
            b=matrix(k,2);
            m1=[a b];
        end 
end
for i=1:size(matrix,1)
      c=matrix(i,1);
        for k=1:size(matrix,2)
            d=matrix(k,2);
            m2 =[c d];
        end
end
if m2==m1
          disp('YOU GOT IT !!');
   end 
matrix

I created 2 vectors m1 and m2 with the values of the first elements and then compare the vectors.

but I dont get any positve results.

采纳的回答

dpb 2015-6-17

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/224261-how-to-compare-a-line-a-of-matrix-with-another#answer_183018

在 MATLAB Online 中打开

>> if size(unique(matrix(:,1:2),'rows'),1)<size(matrix,1)
     disp('Is at least one match')
   else
     disp('All unique')
   end
Is match
>>

5 个评论
显示 3更早的评论隐藏 3更早的评论

Paul Nanfah 2015-6-22

编辑：Paul Nanfah 2015-6-22

sry that the first command was not clear, I actualy meant the command "Is match" at the end of your code seems to be of no use, unless I am wrong.

dpb 2015-6-22

编辑：dpb 2015-6-23

Oh, I see...actually, that's output from the command line, not a command at all (as is shown by it's not preceded by the prompt >> characters and isn't part of a continuing code block as the previous lines from if to the end). I initially had only that string as the disp argument for the match; I expanded it when pasting in the Answer by inserting the "at least one" phrase to make the resulting message more explicit but didn't do the same with the previous output so the two don't match...

请先登录，再进行评论。