Matlab，如何将行矩阵的每个元素与另一个行矩阵的每个元素进行比较？

Question

I have two matrices in Matlab:

q = [3 4 5];  
w = [5 6 7];

I want to compare every element of q with w (ie 3 compared with 5, 6, and 7). If it matches any element in w (like how 5 is in both q and w ) then both q and w share 5 as a common key.

How can I compute all the common keys for q and w ?

Answer 1

Try

>> x = intersect(q,w)

x = 

    5

This function treats the input vectors as sets and returns the set intersection. I think this is what you wanted to know. Is there a match yes/no? if x is empty (numel(x)==0) there was no match.

Answer 2

q = [3 4 5];
w = [5 6 7];

%# @sellibitze
intersect(q,w)

%# @Loren
q( ismember(q,w) )

%# Me :)
q( any(bsxfun(@eq, q, w'),1) )

Answer 3

[Q W] = meshgrid(q, w)
% Q =
%      3     4     5
%      3     4     5
%      3     4     5
% W =
%      5     5     5
%      6     6     6
%      7     7     7
Q == W
% ans =
%      0     0     1
%      0     0     0
%      0     0     0

Answer 4

如果您需要有关匹配的更多信息，请查看ismember，特别是第二和第三输出论据。