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getSolution(ZZ) -- get various attributes of the specified solution

Synopsis

Description

Returns attribute(s) of the i-th solution specified in the optionSolutionAttributes, which could be either a sequence or a single attribute.
SolutionAttributes include:
  • Coordinates -- the list of coordinates
  • SolutionStatus -- REGULAR, SINGULAR, FAILED, etc.
  • NumberOfSteps -- number of steps taken on the corresponding homotopy path
  • LastT -- the last value of the continuation parameter
  • RCondintion-- the reverse condition number at the last step of Newton's method
i1 : R = CC[x,y];
i2 : S = {x^2-1,y^2-1};
i3 : T = {x^2+y^2-1, x*y};
i4 : track(S,T,{(1,1),(1,-1)})

o4 = {{{1, 1.22819e-15}}, {{-4.40616e-16, -1}}}

o4 : List
i5 : getSolution 0

o5 = ({1, 1.22819e-15}, REGULAR, 1, .5, 11)

o5 : Sequence
i6 : getSolution(0, SolutionAttributes=>LastT)

o6 = 1

o6 : RR (of precision 53)
i7 : getSolution(1, SolutionAttributes=>(Coordinates, SolutionStatus, RCondition))

o7 = ({-4.40616e-16, -1}, REGULAR, .5)

o7 : Sequence

Caveat

Requires a preceding run of track or solveSystem with the (default) option Software=>M2engine