RPSWL(A,V)
[Rational polynomial special write,linear. A is a rational polynomial.
V is a variable list for A. A is written in the output stream in a
linearized form which can be read by rpsr. No terminating $]
safe r.
(1) r=LENGTH(V); A'=SDIPFP(r,A); DIPSWL(A',V,1);
return..