I have an optimization problem as below. I am having a hard time with the last constraint.
$\max \eta$
subject to
${\bf U}(:,m)^T{\bf A}{\bf U}(:,m)=0,m=1,2,\cdots,M$
here
$\bf{A}$ is a Binary Matrix of size $N\times N$ (given, known)
$\bf{U}$ is an optimization variable matrix $\bf U$ of size $N\times M$ (Binary matrix)