1. A method to retime a multirate system, comprising: introducing a normalized factor for each node of the multirate system represented by a data flow graph having a plurality of nodes, the normalized factors related to the multiple frequencies of the multirate system; normalizing a plurality of edge delays, retimed solutions, and target clock period of the multirate system according to the normalized factors; defining first retiming constraints for feasibility using normalized edge delays and normalized retimed solutions; defining second retiming constraints to achieve target clock period using normalized target clock periods; defining third retiming constraints for the multirate nodes of the multirate system to be a function of the frequencies of the outgoing and incoming edges of said nodes; finding normalized retimed solutions that satisfy the first, second, and third retiming constraints; and setting retimed edge delays according to the normalized retimed solutions wherein one or more operations above performed by a data processing system.