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NAGtypes :: realPoints

realPoints -- determine whether a point is real

Synopsis

Usage:
R = realPoints L
Inputs:
- L, points
Optional inputs:
- Tolerance => ..., -- specifies the tolerance of a numerical computation
Outputs:
- R, points that are real (up to Tolerance)

Description

i1 : needsPackage "NumericalAlgebraicGeometry"

o1 = NumericalAlgebraicGeometry

o1 : Package

i2 : R = CC[x,y];

i3 : sols = solveSystem{x^6-y^4, x-y-2}

o3 = {{2*ii, -2+2*ii}, {1, -1}, {.937565-.715691*ii, -1.06244-.715691*ii},
     ------------------------------------------------------------------------
     {-2.87513, -4.87513}, {.937565+.715691*ii, -1.06244+.715691*ii}, {-2*ii,
     ------------------------------------------------------------------------
     -2-2*ii}}

o3 : List

i4 : realPoints sols

o4 = {{1, -1}, {-2.87513, -4.87513}}

o4 : List

Ways to use `realPoints` :

realPoints(List)