How to find same unique in two different size arrays?

Question

Ilya Dikariev 2022-6-1

评论： Ilya Dikariev 2022-6-1

Assuming we have two different array sizes with similar items in it. How to find number of common items in these arrays?

for ex:

x=[1 22 22 
   3 8 19];
y=[22 10 19 35];

here answer must be 2, reffering to 22 and 19.

Any good ideas? And also, would that be possible to do it without using loop since actual data size is relatively big?

Answer 1

Fabio Freschi 2022-6-1

Use ismember

% data
x=[1 22 22 
   3 8 19];
y=[22 10 19 35];
% engine
[iii,jjj] = ismember(y(:),x(:));
countCommon = sum(iii)
entryCommon = y(iii)

Ilya Dikariev 2022-6-1

I was scratching my head with two different loops, thanks )