/// <summary>
/// Interpolate, differentiate and 2nd differentiate at point t.
/// </summary>
/// <param name="t">Point t to interpolate at.</param>
/// <returns>Interpolated first derivative at point t.</returns>
/// <seealso cref="IInterpolation.SupportsDifferentiation"/>
/// <seealso cref="Differentiate(double)"/>
public Tuple <double, double, double> DifferentiateAll(double t)
{
return(_spline.DifferentiateAll(t));
}
