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# isRealPoint -- determine whether a point is real

- Usage:
    `b = isRealPoint p`
- Inputs:
  - p
- Optional inputs:
  - Tolerance => ..., default value .000001, the tolerance of a numerical computation
- Outputs:
  - b, tells if p is within Tolerance to a real point

## Description

    i1 : needsPackage "NumericalAlgebraicGeometry"

    o1 = NumericalAlgebraicGeometry

    o1 : Package

    i2 : R = CC[x,y];

    i3 : sols = solveSystem{x^3-y^2, x-y-2}

    o3 = {{-2*ii, -2-2*ii}, {2*ii, -2+2*ii}, {1, -1}}

    o3 : List

    i4 : sols / isRealPoint

    o4 = {false, false, true}

    o4 : List

## Ways to use isRealPoint:

- `isRealPoint(AbstractPoint)`

## For the programmer

The object isRealPoint is a method function with options.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/NAGtypes/doc-NAGtypes.m2:245:0.