Files
QuanTAlib/lib/oscillators/madh/Madh.cs
T

343 lines
10 KiB
C#

using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
namespace QuanTAlib;
/// <summary>
/// MADH: Ehlers Moving Average Difference with Hann
/// </summary>
/// <remarks>
/// A zero-centered percentage oscillator that computes the difference between
/// two Hann-windowed FIR averages (short and long). The long length is derived
/// from the short length plus half the dominant cycle. Pure FIR — no recursive state.
///
/// Calculation:
/// <c>LongLength = (int)(ShortLength + DominantCycle / 2.0)</c>
/// <c>Filt = Σ w(k) · Close[k-1] / Σ w(k) where w(k) = 1 - cos(2π·k / (N+1))</c>
/// <c>MADH = 100 · (Filt1 / Filt2 - 1)</c>
/// </remarks>
/// <seealso href="Madh.md">Detailed documentation</seealso>
/// <seealso href="madh.pine">Reference Pine Script implementation</seealso>
[SkipLocalsInit]
public sealed class Madh : AbstractBase
{
[StructLayout(LayoutKind.Auto)]
private record struct State(int Count, double LastValid)
{
public static State New() => new() { Count = 0, LastValid = 0 };
}
private readonly int _shortLength;
private readonly int _longLength;
private readonly double[] _hannShort;
private readonly double[] _hannLong;
private readonly double _coefSumShort;
private readonly double _coefSumLong;
private State _s = State.New();
private State _ps = State.New();
// RingBuffer stores close prices — needs longLength + 1 slots
private readonly RingBuffer _closeBuf;
private const double Epsilon = 1e-10;
/// <summary>
/// Creates MADH with specified short length and dominant cycle.
/// </summary>
/// <param name="shortLength">Short filter window (must be ≥ 1)</param>
/// <param name="dominantCycle">Dominant cycle estimate (must be ≥ 2)</param>
public Madh(int shortLength = 8, int dominantCycle = 27)
{
if (shortLength < 1)
{
throw new ArgumentOutOfRangeException(nameof(shortLength), shortLength, "ShortLength must be at least 1.");
}
if (dominantCycle < 2)
{
throw new ArgumentOutOfRangeException(nameof(dominantCycle), dominantCycle, "DominantCycle must be at least 2.");
}
_shortLength = shortLength;
_longLength = (int)(shortLength + dominantCycle / 2.0);
// Precompute short Hann window coefficients: w(k) = 1 - cos(2π·k / (N+1))
_hannShort = new double[shortLength];
double angleStepShort = 2.0 * Math.PI / (shortLength + 1);
double sumShort = 0;
for (int k = 1; k <= shortLength; k++)
{
double w = 1.0 - Math.Cos(angleStepShort * k);
_hannShort[k - 1] = w;
sumShort += w;
}
_coefSumShort = sumShort;
// Precompute long Hann window coefficients
_hannLong = new double[_longLength];
double angleStepLong = 2.0 * Math.PI / (_longLength + 1);
double sumLong = 0;
for (int k = 1; k <= _longLength; k++)
{
double w = 1.0 - Math.Cos(angleStepLong * k);
_hannLong[k - 1] = w;
sumLong += w;
}
_coefSumLong = sumLong;
_closeBuf = new RingBuffer(_longLength + 1);
Name = $"Madh({shortLength},{dominantCycle})";
WarmupPeriod = _longLength + 1;
}
/// <summary>
/// Creates MADH with specified source, short length and dominant cycle.
/// Subscribes to source.Pub event.
/// </summary>
public Madh(ITValuePublisher source, int shortLength = 8, int dominantCycle = 27) : this(shortLength, dominantCycle)
{
source.Pub += Handle;
}
/// <summary>
/// Creates MADH with a TSeries source, primes from history, then subscribes.
/// </summary>
public Madh(TSeries source, int shortLength = 8, int dominantCycle = 27) : this(shortLength, dominantCycle)
{
Prime(source.Values);
if (source.Count > 0)
{
Last = new TValue(source.LastTime, Last.Value);
}
source.Pub += Handle;
}
public override bool IsHot => _s.Count > _longLength;
public override void Prime(ReadOnlySpan<double> source, TimeSpan? step = null)
{
if (source.Length == 0)
{
return;
}
_s = State.New();
_ps = State.New();
_closeBuf.Clear();
int len = source.Length;
for (int i = 0; i < len; i++)
{
double val = source[i];
if (double.IsFinite(val))
{
_s.LastValid = val;
}
else
{
val = _s.LastValid;
}
Step(val);
}
Last = new TValue(DateTime.MinValue, ComputeResult());
_ps = _s;
_closeBuf.Snapshot();
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private void Handle(object? sender, in TValueEventArgs e) => Update(e.Value, e.IsNew);
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static double GetValidValue(double input, ref State s)
{
if (double.IsFinite(input))
{
s.LastValid = input;
return input;
}
return s.LastValid;
}
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
public override TValue Update(TValue input, bool isNew = true)
{
if (isNew)
{
_ps = _s;
_closeBuf.Snapshot();
}
else
{
_s = _ps;
_closeBuf.Restore();
}
double val = GetValidValue(input.Value, ref _s);
Step(val);
double result = ComputeResult();
Last = new TValue(input.Time, result);
PubEvent(Last, isNew);
return Last;
}
[MethodImpl(MethodImplOptions.AggressiveOptimization)]
public override TSeries Update(TSeries source)
{
if (source.Count == 0)
{
return [];
}
int len = source.Count;
var t = new List<long>(len);
var v = new List<double>(len);
CollectionsMarshal.SetCount(t, len);
CollectionsMarshal.SetCount(v, len);
var tSpan = CollectionsMarshal.AsSpan(t);
var vSpan = CollectionsMarshal.AsSpan(v);
source.Times.CopyTo(tSpan);
Reset();
for (int i = 0; i < len; i++)
{
double val = source.Values[i];
if (double.IsFinite(val))
{
_s.LastValid = val;
}
else
{
val = _s.LastValid;
}
Step(val);
vSpan[i] = ComputeResult();
}
_ps = _s;
_closeBuf.Snapshot();
Last = new TValue(tSpan[len - 1], vSpan[len - 1]);
return new TSeries(t, v);
}
/// <summary>
/// Core streaming step: add close price to ring buffer.
/// </summary>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private void Step(double input)
{
_s.Count++;
_closeBuf.Add(input);
}
/// <summary>
/// Computes MADH from the close buffer using dual Hann-weighted FIR averages.
/// </summary>
[MethodImpl(MethodImplOptions.AggressiveInlining | MethodImplOptions.AggressiveOptimization)]
private double ComputeResult()
{
int available = Math.Min(_s.Count, _longLength + 1);
if (available <= 0)
{
return 0.0;
}
// Short Hann FIR: scan most recent shortLength values
double sumShort = 0.0;
int effectiveShort = Math.Min(available, _shortLength);
for (int k = 1; k <= effectiveShort; k++)
{
double val = _closeBuf[available - k];
sumShort = Math.FusedMultiplyAdd(_hannShort[k - 1], val, sumShort);
}
double filt1 = _coefSumShort > Epsilon ? sumShort / _coefSumShort : 0.0;
// Long Hann FIR: scan most recent longLength values
double sumLong = 0.0;
int effectiveLong = Math.Min(available, _longLength);
for (int k = 1; k <= effectiveLong; k++)
{
double val = _closeBuf[available - k];
sumLong = Math.FusedMultiplyAdd(_hannLong[k - 1], val, sumLong);
}
double filt2 = _coefSumLong > Epsilon ? sumLong / _coefSumLong : 0.0;
return Math.Abs(filt2) > Epsilon ? 100.0 * (filt1 / filt2 - 1.0) : 0.0;
}
/// <summary>
/// Batch calculation returning a TSeries.
/// </summary>
public static TSeries Batch(TSeries source, int shortLength = 8, int dominantCycle = 27)
{
var indicator = new Madh(shortLength, dominantCycle);
return indicator.Update(source);
}
/// <summary>
/// Batch calculation writing to a pre-allocated output span. Zero-allocation hot path.
/// </summary>
public static void Batch(ReadOnlySpan<double> source, Span<double> output, int shortLength = 8, int dominantCycle = 27)
{
if (source.Length != output.Length)
{
throw new ArgumentException("Source and output must have the same length", nameof(output));
}
if (shortLength < 1)
{
throw new ArgumentOutOfRangeException(nameof(shortLength), shortLength, "ShortLength must be at least 1.");
}
if (dominantCycle < 2)
{
throw new ArgumentOutOfRangeException(nameof(dominantCycle), dominantCycle, "DominantCycle must be at least 2.");
}
if (source.Length == 0)
{
return;
}
var indicator = new Madh(shortLength, dominantCycle);
for (int i = 0; i < source.Length; i++)
{
double val = source[i];
if (double.IsFinite(val))
{
indicator._s.LastValid = val;
}
else
{
val = indicator._s.LastValid;
}
indicator.Step(val);
output[i] = indicator.ComputeResult();
}
}
/// <summary>
/// Creates a hot indicator from historical data, ready for streaming.
/// </summary>
public static (TSeries Results, Madh Indicator) Calculate(TSeries source, int shortLength = 8, int dominantCycle = 27)
{
var indicator = new Madh(shortLength, dominantCycle);
TSeries results = indicator.Update(source);
return (results, indicator);
}
public override void Reset()
{
_s = State.New();
_ps = _s;
_closeBuf.Clear();
Last = default;
}
}