Abstract

As most of you may already know, there is the program P4 (Planar Polynomial Phase Portraits) which studies the local behaviour and global phase portrait of Planar Polynomial Differential Systems. Many mathematicians are already using it for what it was designed, but some have tried to use it in other fields, concretely, they have tried to use it in planar problems where several differential systems are in action in different regions of the plane. That is quite common in problems in electronics and control theory. Since the results were not completely satisfactory, the team of authors have developed a new complete software (based on P4) to deal with this problem. The name P5 is not just a numerical evolution of P4 but it stands for Piecewise Planar Polynomial Phase Portraits.