Generalized Linear Differential Operator Commutator

Computes commuted expansion coefficients for linear operators.

Given a generalizd linear differential operator:

L=a_N(x)D^N+...+a_1(x)D+a_0(x)

where the variable coefficients are polynomials, this script finds the new variable coefficients

L=D^N b_N(x)+...+D b_1(x)+b_0(x)

so that the derivatives are moved to the left. This is desireable when forming an integral equation from a diffential equation.