could anyone help me how to fix this issue.

If there are 10 users (say user1,user2 and goes on till user10) present how to group the users under the following conditions ->2 users should be present in each group. ->users present in one group should not be present in other group. and the possible number of combinations they can form.

[Adam]

You haven't shown anything to 'fix'. You appear to have just copied part of a question in with no attempt shown at solving it yourself.

[Guillaume]

And there isn't even a complete question. It's not clear what is being asked. Do the 945 possible combinations (for 10 users) have to be generated, or just the number of possible combinations calculated (something that is trivial to do)?

[Prabha Kumaresan]

all the possible combinations needs to be generated

[Stephen23]

@Prabha Kumaresan: what have you tried so far? Your question asks if anyone can "fix this issue", but you haven't given us anything to "fix".

[Prabha Kumaresan]

unused_rows = 1:10;
N_UE_rows   = 2;
rows=unused_rows(randsample(length(unused_rows), N_UE_rows));

This was the code i need to fix it

[Guillaume]

"This was the code i need to fix it"

That doesn't like code that even attempt at doing what is being ask. The fix here is to start from scratch.

The whole purpose of this sort of homework exercice is to teach you how to design an algorithm that solve a particular problem. Going through the thought process required to solve the problem is the most important part of that task. If we give you the algorithm, then you will not have learnt that process. That would be a great disservice to you.

Once you have figured out the algorithm coding it is only a 5 minutes job.

[Rik]

@Guillaume, I doubt this is a homework question. Prabha Kumaresan has posted an impressive number of questions about code very similar to this already.