We are studing the simulator to use it in a project , we worked with the schedulers. We find this:
That rand is in case of a tie in the best CQI in a particular RB. If you see the previous lines at line 43 the scheduler finds the maxCQI value for each RB, at lines 45-51 the scheduler finds the users with that value of CQI (the max value) in each RB,in case of more than one user with the value of max CQI in a RB the scheduler selects one of that users randomly.
I hope you find this helpful .