Sma.cs

public static List<double?> Sma(this List<double> source, int period = 30)
{
    int outBegIdx, outNbElement;
    double[] smaValues = new double[source.Count];
    List<double?> outValues = new List<double?>();

    var sma = TA.Library.Core.Sma(0, source.Count - 1, source.ToArray(), period, out outBegIdx, out outNbElement, smaValues);

    if (sma == TA.Library.Core.RetCode.Success)
    {
        FixIndicatorOrdering(smaValues.ToList(), outBegIdx, outNbElement);
    }

    throw new Exception("Could not calculate SMA!");
}