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segmentHomotopy -- a segment homotopy

Description

This method produces a Homotopy (1-t) S+ t \gamma T, t\in[0,1].

i1 : R = QQ[x,y]

o1 = R

o1 : PolynomialRing
i2 : T = {random(3,R)-1, random(2,R)-2}

      9 3   9 2    3   2   7 3      7 2    7       7 2
o2 = {-x  + -x y + -x*y  + -y  - 1, -x  + --x*y + --y  - 2}
      2     4      4       4        9     10      10

o2 : List
i3 : (S,solsS) = totalDegreeStartSystem T

        3       2
o3 = ({x  - 1, y  - 1}, {{1, -1}, {-.5-.866025*ii, -1}, {-.5+.866025*ii, -1},
     ------------------------------------------------------------------------
     {-.5-.866025*ii, 1}, {1, 1}, {-.5+.866025*ii, 1}})

o3 : Sequence
i4 : H = segmentHomotopy(S,T,gamma=>1+ii)

o4 = GateHomotopy{...11...}

o4 : GateHomotopy
i5 : evaluateH(H,transpose matrix first solsS,0)

o5 = | 0              |
     | -2.44929e-16ii |

                2         1
o5 : Matrix CC    <-- CC
              53        53

Ways to use segmentHomotopy:

  • segmentHomotopy(GateSystem,GateSystem)
  • segmentHomotopy(List,List)
  • segmentHomotopy(PolySystem,PolySystem)

For the programmer

The object segmentHomotopy is a method function with options.


The source of this document is in NumericalAlgebraicGeometry/doc.m2:1422:0.