public void Add(DateTime dtTime, double dValue, int iID = 0, string sTag = "")
        {
            DateTimePlotPoint dtPoint = new DateTimePlotPoint();

            dtPoint.Time  = dtTime;
            dtPoint.Value = dValue;
            dtPoint.ID    = iID;
            dtPoint.Tag   = sTag;
            aList.Add(dtPoint);
        }
 // Indexer: get the Sample instance at the specified ordinal position in the list
 public PointPair this[int index]
 {
     get
     {
         PointPair         pt     = new PointPair();
         DateTimePlotPoint aPoint = aList[index];
         pt.X   = GetValue(aPoint, XType);
         pt.Y   = GetValue(aPoint, YType);
         pt.Tag = aPoint.Tag;
         return(pt);
     }
     set
     {
     }
 }
        // Get the specified data type from the specified sample
        public double GetValue(DateTimePlotPoint Point, DateTimePointType Type)
        {
            switch (Type)
            {
            case DateTimePointType.Time:
                return(Point.Time.ToOADate());

            case DateTimePointType.Value:
                return(Point.Value);

            case DateTimePointType.ID:
                return(Point.ID);

            default:
                return(PointPair.Missing);
            }
        }
 // Add a sample to the collection
 public void Add(DateTimePlotPoint dtPoint)
 {
     aList.Add(dtPoint);
 }