Demonstration program for using CAS with PPL

[Michael de Estrada]

Your modification has one serious drawback; namely you can't run Beam2_Solve directly, since the parameter matrix has to be evaluated each time the program is run. The reason I wrote the program that way and exported Beam2_Solve was to permit initial entry of the matrix parameters through Beam2_Main to obtain an initial root, and then run Beam2_Solve repeatedly to obtain additional roots w/o having to re-enter all the beam parameters, which don't change. This is why I chose to make the matrix a global CAS variable. I agree, however, that it wasn't necessary to make the individual matrix coefficients into permanent CAS variables.