/// <summary>
/// Creates a piece-linear function from the grapher points array
/// and then a FunctionGrapher object.
///
/// This trick allows the grapher to behave more smoothly during scaling,
/// no points usually are 'lost'.
/// </summary>
/// <returns></returns>
public static FunctionGrapher CreateSmoothPieceLinearGrapher(this StandardGrapher obj)
{
IFunction <double, double> function = Interpolation <double, CalcDouble> .CreatePieceLinearFunction(obj.GetPointsArray(), double.NaN);
return(new FunctionGrapher(function));
}