PostScript lacks a lot of basic operators such as tan, acos, asin, cosh, sinh, tanh, acosh, asinh, atanh, exp (with e base). Also (oddly) cos and sin use arguments in degrees. Pst-math provides all those operators in a header file pst-math.pro with wrappers pst-math.sty and pst-math.tex. In addition, sinc, gauss, gammaln and bessel are implemented (only partially for the latter). The package is designed essentially to work with pst-plot but can be used in whatever PS code (such as PSTricks SpecialCoor "!", which is useful for placing labels). The package also provides a routine SIMPSON for numerical integration and a solver of linear equation systems.