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Dmodules :: globalB(Ideal,RingElement)

globalB(Ideal,RingElement) -- compute global b-function and b-operator for a D-module and a polynomial

Synopsis

Description

The algorithm used here is a modification of the original algorithm of Oaku for computing Bernstein-Sato polynomials
i1 : R = QQ[x, dx, WeylAlgebra => {x=>dx}]

o1 = R

o1 : PolynomialRing, 1 differential variables
i2 : f = x^7

      7
o2 = x

o2 : R
i3 : b = globalB(ideal dx, f)

                              7
o3 = HashTable{Boperator => dx                                                                                   }
                                     7           6           5           4           3          2
               Bpolynomial => 823543s  + 3294172s  + 5411854s  + 4705960s  + 2321767s  + 643468s  + 91476s + 5040

o3 : HashTable
i4 : factorBFunction b.Bpolynomial 

                 1      2      3      4      5      6
o4 = (s + 1)(s + -)(s + -)(s + -)(s + -)(s + -)(s + -)
                 7      7      7      7      7      7

o4 : Expression of class Product

See also