TRIGMAN: A System for Algebraic Manipulation of Poisson Series. The TRIGMAN system, manipulates Poisson Series (trignometric series with polynomial coefficients). It consists of a set of FORTRAN preprocessor written in SNOBOL and a set of FORTRAN subroutine for elementary symbolic operations. The TRIGMAN source language resembles FORTRAN but with additional declarations. Programs are translated into legal FORTRAN then compiled.