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NAGtypes :: witnessSet

witnessSet -- construct a WitnessSet

Synopsis

Description

Used to construct a witness set of the variety V(E). It is expected that codim E == dim S and that P is a subset of the intersection of V(E) and V(S).

i1 : R = CC[x,y]     

o1 = R

o1 : PolynomialRing
i2 : w = witnessSet( ideal(x^2+y^2+2), ideal(x-y), {point {{0.999999*ii,0.999999*ii}}, point {{-1.000001*ii,-1.000001*ii}}} )

o2 = (dim=1,deg=2)

o2 : WitnessSet
i3 : peek w

o3 = WitnessSet{IsIrreducible => null               }
                Points => {{.999999*ii, .999999*ii}}
                          {{-ii, -ii}              }
                Slice => {x - y}
                                    2    2
                Equations => ideal(x  + y  + 2)

Ways to use witnessSet :