dev branch

lib/averages/Smma.cs

@@ -0,0 +1,78 @@
+using System;
+
+namespace QuanTAlib;
+
+public class Smma : AbstractBase
+{
+    private readonly int _period;
+    private CircularBuffer? _buffer;
+    private double _lastSmma, _p_lastSmma;
+
+    public Smma(int period) 
+    {
+        if (period < 1)
+        {
+            throw new ArgumentException("Period must be greater than or equal to 1.", nameof(period));
+        }
+        _period = period;
+        WarmupPeriod = period;
+        Name = $"Smma({_period})";
+        Init();
+    }
+
+    public Smma(object source, int period) : this(period)
+    {
+        var pubEvent = source.GetType().GetEvent("Pub");
+        pubEvent?.AddEventHandler(source, new ValueSignal(Sub));
+    }
+
+    public override void Init()
+    {
+        base.Init();
+        _buffer = new CircularBuffer(_period);
+        _lastSmma = 0;
+    }
+
+    protected override void ManageState(bool isNew)
+    {
+        if (isNew)
+        {
+            _lastValidValue = Input.Value;
+            _p_lastSmma = _lastSmma;
+            _index++;
+        }
+        else
+        {
+            _lastSmma = _p_lastSmma;
+        }
+    }
+
+
+    protected override double Calculation()
+    {
+        ManageState(Input.IsNew);
+
+        _buffer!.Add(Input.Value, Input.IsNew);
+
+        double smma;
+
+        if (_index <= _period)
+        {
+            smma = _buffer.Average();
+
+            if (_index == _period)
+            {
+                _lastSmma = smma; // Initialize _lastSmma for the transition
+            }
+        }
+        else
+        {
+            smma = ((_lastSmma * (_period - 1)) + Input.Value) / _period;
+        }
+
+        _lastSmma = smma;
+        IsHot = _index >= WarmupPeriod;
+
+        return smma;
+    }
+}