localPrune -- find a minimal presentation

Synopsis

• Usage:

  localPrune M

• Inputs:

  • M, a module
• Outputs:

  • a module

Description

i1 : R=QQ[a,b]

o1 = R

o1 : PolynomialRing

i2 : setMaxIdeal ideal gens R

o2 = ideal (a, b)

o2 : Ideal of R

i3 : m = matrix{{a-1,a,b},{a-1,a,b}}

o3 = | a-1 a b |
     | a-1 a b |

             2       3
o3 : Matrix R  <--- R

i4 : prune m

o4 = | a-1 a b |
     | a-1 a b |

             2       3
o4 : Matrix R  <--- R

i5 : localPrune image m

      1
o5 = R

o5 : R-module, free, degrees {1}

See also

• setMaxIdeal -- set the maximal ideal for local ring methods
• localComplement -- find the splitting of the target of a map
• localsyz -- find syzygies
• localMingens -- finds a minimal set of generators
• localModulo -- find the pre-image (pullback) of image of a map over a local ring
• localResolution -- find a resolution over a local ring
• residueMap (missing documentation)
• maxIdeal (missing documentation)