Update RSI_Series to check for period != 0 before calculating RSI

Calculations/_Updated/DWMA_Series.cs

@@ -0,0 +1,126 @@
+namespace QuanTAlib;
+
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+/* <summary>
+DWMA: Double Weighted Moving Average
+    The weights are decreasing over the period with p^2 decay
+		and the most recent data has the heaviest weight.
+
+</summary> */
+
+public class DWMA_Series : TSeries {
+	private readonly List<double> _buffer = new();
+	private List<double> _weights = new();
+	protected readonly int _period;
+	protected readonly bool _NaN;
+	protected readonly TSeries _data;
+	protected int _len;
+
+//core constructors
+	public DWMA_Series(int period, bool useNaN) : base() {
+		_period = period;
+		_NaN = useNaN;
+		Name = $"DWMA({period})";
+		_len = 0;
+		_weights = CalculateWeights(_period);
+	}
+
+	public DWMA_Series(TSeries source, int period, bool useNaN) : this(period, useNaN) {
+		_data = source;
+		Name = Name.Substring(0, Name.IndexOf(")")) + $", {(string.IsNullOrEmpty(_data.Name) ? "data" : _data.Name)})";
+		_data.Pub += Sub;
+		Add(_data);
+	}
+
+	public DWMA_Series() : this(0, false) {
+	}
+
+	public DWMA_Series(int period) : this(period, false) {
+	}
+
+	public DWMA_Series(TBars source) : this(source.Close, 0, false) {
+	}
+
+	public DWMA_Series(TBars source, int period) : this(source.Close, period, false) {
+	}
+
+	public DWMA_Series(TBars source, int period, bool useNaN) : this(source.Close, period, useNaN) {
+	}
+
+	public DWMA_Series(TSeries source, int period) : this(source, period, false) {
+	}
+
+	//////////////////
+	// core Add() algo
+	public override (DateTime t, double v) Add((DateTime t, double v) TValue, bool update = false) {
+		BufferTrim(_buffer, TValue.v, _period, update);
+		if (_period == 0) {
+			_len++;
+			_weights = CalculateWeights(_len);
+		}
+
+		double _dwma = 0, _wsum = 0;
+		var bufferCount = _buffer.Count;
+
+		var lockObj = new object();
+		Parallel.For(0, bufferCount, i =>
+		{
+			var temp = _buffer[i] * _weights[i];
+			lock (lockObj) {
+				_dwma += temp;
+				_wsum += _weights[i];
+			}
+		});
+		_dwma /= _wsum;
+		var res = (TValue.t, Count < _period - 1 && _NaN ? double.NaN : _dwma);
+		return base.Add(res, update);
+	}
+
+	public override (DateTime t, double v) Add(TSeries data) {
+		if (data == null) {
+			return (DateTime.Today, double.NaN);
+		}
+
+		foreach (var item in data) {
+			Add(item, false);
+		}
+
+		return _data.Last;
+	}
+
+	public new (DateTime t, double v) Add((DateTime t, double v) TValue) {
+		return Add(TValue, false);
+	}
+
+	public (DateTime t, double v) Add(bool update) {
+		return Add(_data.Last, update);
+	}
+
+	public (DateTime t, double v) Add() {
+		return Add(_data.Last, false);
+	}
+
+	private new void Sub(object source, TSeriesEventArgs e) {
+		Add(_data.Last, e.update);
+	}
+
+	//calculating weights
+	private static List<double> CalculateWeights(int period) {
+		var weights = new List<double>(period);
+		for (var i = 0; i < period; i++) {
+			weights.Add((i + 1) * (i + 1));
+		}
+
+		return weights;
+	}
+
+	//reset calculation
+	public override void Reset() {
+		_len = 0;
+		_buffer.Clear();
+		_weights = CalculateWeights(_period);
+	}
+}