bfunction

 a bfunction b
array a; poly b;
a :  [f] ;  string f ;
a :  [f] ;  polynomial f ;
a :  [f v] ; string f,v; 
a :  [f v] ; polynomial f, string v; 
b is the b-function (=Bernstein-Sato polynomial) of a polynomial f
in variables v.
If v is not specified, the variables are assumed to be (x,y,z). 
b will be a polynomial in s.  This variable can be changed by typing in
  (variable) /bfunction.s set 
For the algorithm, see Duke Math. J. 87 (1997),115-132,
   J. Pure and Applied Algebra 117&118(1997), 495--518.
Example  [(x^3-y^2) (x,y)] bfunction ::