match row and column

I have one matrix

a=
1 3 0
2 5 0
3 7 0
4 8 0
5 10 0

and another is

b=
5 10
3 7

I want to do find(a(:,1)=b(:,1) & a(:,2)==b(:,2) so that

5 10 0
3 7 0

Answer 1

[Stephen23]

You can use ismember to generate the logical indices. In the same order as a:

>> idx = ismember(a(:,1:2),b,'rows');
>> a(idx,:)
ans =
    3    7    0
    5   10    0

Or in the same order as b:

>> [~,idx] = ismember(b,a(:,1:2),'rows');
>> a(idx,:)
ans =
    5   10    0
    3    7    0