replace in-place division operator to avoid dtype issue in int/float
replace in-place division operator to avoid dtype issue in int/float

manuelli/director,manuelli/director,manuelli/director,openhumanoids/director,mitdrc/director,patmarion/director,patmarion/director,mitdrc/director,patmarion/director,openhumanoids/director,openhumanoids/director,RobotLocomotion/director,manuelli/director,RobotLocomotion/director,mitdrc/director,RobotLocomotion/director,patmarion/director,manuelli/director,openhumanoids/director,patmarion/director,openhumanoids/director,mitdrc/director,mitdrc/director,RobotLocomotion/director,RobotLocomotion/director