Related Layout Systems

In addition to the MIT implementation of PI there have been two other significant implementations of PI: 2PI and EC-PI. This chapter describes these two variations of PI which were developed respectively at the General Electric Research and Development Center and at the Technion in Israel. 2PI extends PI in several ways to make PI more convenient to use in an industrial setting; EC-PI follows PI’s problem decomposition but changes some of the component algorithms. This chapter also describes selected other layout systems—including the Magic, Phoenix, and TimberWolf systems—and points out many of the significant layout systems that came before and after PI.