The original problem I have is

```
for i=1:L
for j=1:L
for n=1:N
if W(i,j)>0 and i<j
z(i,j)>=X(i,n)+X(j,n)-1;
end
end
end
end
```

where W (L,L) is a known matrix and is symmetric. X(L,N) is optimization variable.

So, I tried to reduce the size of the problem by extracting all the pairs (i,j) for which W(i,j)>0. So, I removed the if condition.

Now, let’s says there are M such pairs.

veca contains the i’s

vecb contains the j’s

Now, the constraint becomes

```
for m=1:M
for n=1:N
z(m)>=X(veca(m),n)+ X(vecb(m),n)-1;
end
end
```

Am I not doing i right?

If it is correct, I don’t know why it is taking so long for the CVX/solver to solve this? It is taking forever!