Dprune -- prunes a D-module

Synopsis

• Usage:

  Dprune M

• Inputs:
  • M, a matrix or a module
• Optional inputs:
  • optGB => ..., default value true, indicates whether a Grobner basis should be computed
• Outputs:
  • a matrix or a module of the same type as M

Description

i1 : W = makeWA(QQ[x,y])

o1 = W

o1 : PolynomialRing, 2 differential variables

i2 : M = matrix{{x,dx},{1,1}} 

o2 = | x dx |
     | 1 1  |

             2       2
o2 : Matrix W  <--- W

i3 : Dprune M

o3 = | x-dx |

             1       1
o3 : Matrix W  <--- W

i4 : Dprune coker M

o4 = cokernel | x-dx |

                            1
o4 : W-module, quotient of W

i5 : M = matrix{{x,dx},{x,y}}

o5 = | x dx |
     | x y  |

             2       2
o5 : Matrix W  <--- W

i6 : Dprune M

o6 = | dx x xy-xdx |
     | y  x 0      |

             2       3
o6 : Matrix W  <--- W

See also

• pruneCechComplexCC -- reduction of the Cech complex that produces characteristic cycles of local cohomology modules