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Miha Kralj 060649192f docs: remove C# Implementation Considerations sections, clean up temp scripts, reorganize test files
- Remove 'C# Implementation Considerations' sections from 34 indicator .md files
- Delete 29 temp PowerShell scripts (_fix_mojibake.ps1, _hex_scan.ps1, etc.)
- Move test files into tests/ subdirectories for consistent project structure
- Add trader-focused bullet points to indicator documentation
2026-03-12 12:34:16 -07:00

371 lines
11 KiB
C#

namespace QuanTAlib.Tests;
public class TheilUTests
{
private const double Precision = 1e-10;
private const int DefaultPeriod = 10;
[Fact]
public void Constructor_ValidatesInput()
{
Assert.Throws<ArgumentException>(() => new TheilU(0));
Assert.Throws<ArgumentException>(() => new TheilU(-1));
}
[Fact]
public void Constructor_ValidPeriod_Succeeds()
{
var theilU = new TheilU(DefaultPeriod);
Assert.NotNull(theilU);
Assert.Equal(DefaultPeriod, theilU.WarmupPeriod);
}
[Fact]
public void Properties_Accessible()
{
var theilU = new TheilU(DefaultPeriod);
Assert.Contains("TheilU", theilU.Name, StringComparison.Ordinal);
Assert.False(theilU.IsHot);
Assert.Equal(0, theilU.Last.Value);
}
[Fact]
public void IsHot_BecomesTrueWhenBufferFull()
{
var theilU = new TheilU(5);
for (int i = 0; i < 4; i++)
{
theilU.Update(100 + i, 100);
Assert.False(theilU.IsHot);
}
theilU.Update(104, 100);
Assert.True(theilU.IsHot);
}
[Fact]
public void Calculate_PerfectForecast_ReturnsZero()
{
// U = 0 for perfect forecast
var theilU = new TheilU(5);
for (int i = 0; i < 5; i++)
{
theilU.Update(100, 100);
}
Assert.Equal(0.0, theilU.Last.Value, Precision);
}
[Fact]
public void Calculate_ReturnsCorrectValue()
{
// TheilU = √(Σ(pred-act)²) / √(Σact² + Σpred²)
var theilU = new TheilU(2);
// Actual: 100, 100 -> sum of squares = 20000
// Predicted: 110, 90 -> sum of squares = 12100 + 8100 = 20200
// Errors: 10, -10 -> sum of squared errors = 200
// TheilU = √200 / √(20000 + 20200) = √200 / √40200
theilU.Update(100, 110);
theilU.Update(100, 90);
double expected = Math.Sqrt(200) / Math.Sqrt(20000 + 20200);
Assert.Equal(expected, theilU.Last.Value, Precision);
}
[Fact]
public void Calculate_BoundedZeroToOne_ForReasonableForecasts()
{
var theilU = new TheilU(5);
var gbm = new GBM(startPrice: 100.0, mu: 0.02, sigma: 0.1, seed: 42);
// Run with reasonable prediction errors
for (int i = 0; i < 10; i++)
{
var bar = gbm.Next(isNew: true);
theilU.Update(bar.Close, bar.Close * 0.95); // 5% prediction error
}
Assert.True(theilU.Last.Value >= 0.0);
Assert.True(theilU.Last.Value <= 1.0);
}
[Fact]
public void Calculate_IsNew_False_UpdatesValue()
{
var theilU = new TheilU(DefaultPeriod);
theilU.Update(100, 95);
theilU.Update(110, 108, isNew: true);
double beforeUpdate = theilU.Last.Value;
theilU.Update(110, 100, isNew: false);
double afterUpdate = theilU.Last.Value;
Assert.NotEqual(beforeUpdate, afterUpdate);
}
[Fact]
public void IterativeCorrections_RestoreToOriginalState()
{
var theilU = new TheilU(5);
var gbm = new GBM(startPrice: 100.0, mu: 0.02, sigma: 0.1);
TValue tenthActual = default;
TValue tenthPredicted = default;
for (int i = 0; i < 10; i++)
{
var bar = gbm.Next(isNew: true);
tenthActual = new TValue(bar.Time, bar.Close);
tenthPredicted = new TValue(bar.Time, bar.Close * 0.98);
theilU.Update(tenthActual, tenthPredicted, isNew: true);
}
double stateAfterTen = theilU.Last.Value;
for (int i = 0; i < 9; i++)
{
var bar = gbm.Next(isNew: false);
theilU.Update(new TValue(bar.Time, bar.Close), new TValue(bar.Time, bar.Close * 0.95), isNew: false);
}
TValue finalResult = theilU.Update(tenthActual, tenthPredicted, isNew: false);
Assert.Equal(stateAfterTen, finalResult.Value, Precision);
}
[Fact]
public void Reset_ClearsState()
{
var theilU = new TheilU(DefaultPeriod);
theilU.Update(100, 95);
theilU.Update(105, 100);
theilU.Reset();
Assert.Equal(0, theilU.Last.Value);
Assert.False(theilU.IsHot);
}
[Fact]
public void NaN_Input_UsesLastValidValue()
{
var theilU = new TheilU(DefaultPeriod);
theilU.Update(100, 95);
theilU.Update(110, 105);
var result = theilU.Update(double.NaN, 108);
Assert.True(double.IsFinite(result.Value));
result = theilU.Update(115, double.NaN);
Assert.True(double.IsFinite(result.Value));
}
[Fact]
public void Infinity_Input_UsesLastValidValue()
{
var theilU = new TheilU(DefaultPeriod);
theilU.Update(100, 95);
theilU.Update(110, 105);
var result = theilU.Update(double.PositiveInfinity, 108);
Assert.True(double.IsFinite(result.Value));
result = theilU.Update(115, double.NegativeInfinity);
Assert.True(double.IsFinite(result.Value));
}
[Fact]
public void BatchCalc_MatchesIterativeCalc()
{
var theilUIterative = new TheilU(DefaultPeriod);
var gbm = new GBM(startPrice: 100.0, mu: 0.02, sigma: 0.1, seed: 42);
var actualSeries = new TSeries();
var predictedSeries = new TSeries();
var iterativeResults = new List<double>();
for (int i = 0; i < 100; i++)
{
var bar = gbm.Next(isNew: true);
double predicted = bar.Close * (1 + (i % 2 == 0 ? 0.02 : -0.02));
actualSeries.Add(bar.Time, bar.Close);
predictedSeries.Add(bar.Time, predicted);
iterativeResults.Add(theilUIterative.Update(new TValue(bar.Time, bar.Close), new TValue(bar.Time, predicted)).Value);
}
var batchResults = TheilU.Batch(actualSeries, predictedSeries, DefaultPeriod);
Assert.Equal(iterativeResults.Count, batchResults.Count);
for (int i = 0; i < iterativeResults.Count; i++)
{
Assert.Equal(iterativeResults[i], batchResults[i].Value, Precision);
}
}
[Fact]
public void SpanBatch_ValidatesInput()
{
double[] actual = [1, 2, 3, 4, 5];
double[] predicted = [1.1, 2.1, 3.1, 4.1, 5.1];
double[] output = new double[5];
double[] wrongSizeOutput = new double[3];
Assert.Throws<ArgumentException>(() =>
TheilU.Batch(actual.AsSpan(), predicted.AsSpan(), wrongSizeOutput.AsSpan(), DefaultPeriod));
Assert.Throws<ArgumentException>(() =>
TheilU.Batch(actual.AsSpan(), predicted.AsSpan(), output.AsSpan(), 0));
}
[Fact]
public void SpanBatch_MatchesTSeriesBatch()
{
var gbm = new GBM(startPrice: 100.0, mu: 0.02, sigma: 0.1, seed: 42);
var actualSeries = new TSeries();
var predictedSeries = new TSeries();
double[] actualArr = new double[100];
double[] predictedArr = new double[100];
double[] output = new double[100];
for (int i = 0; i < 100; i++)
{
var bar = gbm.Next(isNew: true);
actualSeries.Add(bar.Time, bar.Close);
actualArr[i] = bar.Close;
double pred = bar.Close * 0.98;
predictedSeries.Add(bar.Time, pred);
predictedArr[i] = pred;
}
var tseriesResult = TheilU.Batch(actualSeries, predictedSeries, DefaultPeriod);
TheilU.Batch(actualArr.AsSpan(), predictedArr.AsSpan(), output.AsSpan(), DefaultPeriod);
for (int i = 0; i < 100; i++)
{
Assert.Equal(tseriesResult[i].Value, output[i], Precision);
}
}
[Fact]
public void SpanBatch_HandlesNaN()
{
double[] actual = [100, 110, double.NaN, 120, 130];
double[] predicted = [98, 108, 112, 118, double.NaN];
double[] output = new double[5];
TheilU.Batch(actual.AsSpan(), predicted.AsSpan(), output.AsSpan(), 3);
foreach (var val in output)
{
Assert.True(double.IsFinite(val), $"Expected finite value but got {val}");
}
}
[Fact]
public void Update_ThrowsOnSingleInput()
{
var theilU = new TheilU(DefaultPeriod);
Assert.Throws<NotSupportedException>(() => theilU.Update(new TValue(DateTime.UtcNow, 100)));
}
[Fact]
public void Prime_ThrowsNotSupported()
{
var theilU = new TheilU(DefaultPeriod);
Assert.Throws<NotSupportedException>(() => theilU.Prime([1, 2, 3]));
}
[Fact]
public void Calculate_MismatchedSeriesLengths_Throws()
{
var actual = new TSeries();
var predicted = new TSeries();
actual.Add(DateTime.UtcNow.Ticks, 100);
actual.Add(DateTime.UtcNow.Ticks + 1, 110);
predicted.Add(DateTime.UtcNow.Ticks, 98);
Assert.Throws<ArgumentException>(() => TheilU.Batch(actual, predicted, DefaultPeriod));
}
[Fact]
public void Resync_PreventsFloatingPointDrift()
{
// Test that resync keeps values accurate over many updates
var theilU = new TheilU(5);
var gbm = new GBM(startPrice: 100.0, mu: 0.02, sigma: 0.1, seed: 42);
// Run more than ResyncInterval (1000) updates
for (int i = 0; i < 1100; i++)
{
var bar = gbm.Next(isNew: true);
theilU.Update(bar.Close, bar.Close * 0.98);
}
Assert.True(double.IsFinite(theilU.Last.Value));
Assert.True(theilU.Last.Value >= 0);
Assert.True(theilU.Last.Value <= 1); // Should be bounded
}
[Fact]
public void Calculate_ZeroValues_ReturnsZero()
{
// When denominator is near zero, should return 0 (epsilon protection)
var theilU = new TheilU(3);
theilU.Update(0.0, 0.0);
theilU.Update(0.0, 0.0);
theilU.Update(0.0, 0.0);
Assert.Equal(0.0, theilU.Last.Value, Precision);
}
[Fact]
public void Calculate_ScaleIndependent()
{
// TheilU should be scale-independent (relative measure)
var theilU1 = new TheilU(3);
var theilU2 = new TheilU(3);
// Scale 1
theilU1.Update(100, 110);
theilU1.Update(100, 90);
theilU1.Update(100, 105);
// Scale 1000 (same relative errors)
theilU2.Update(100000, 110000);
theilU2.Update(100000, 90000);
theilU2.Update(100000, 105000);
Assert.Equal(theilU1.Last.Value, theilU2.Last.Value, Precision);
}
[Fact]
public void Calculate_SymmetricErrors()
{
// Note: Theil's U is NOT symmetric with respect to direction because
// the denominator includes √(Σact² + Σpred²) where pred differs.
// However, the squared error in the numerator treats positive and
// negative errors the same way.
var theilU1 = new TheilU(2);
var theilU2 = new TheilU(2);
// Predict 10% above: errors = (100-110)² = 100 each
theilU1.Update(100, 110);
theilU1.Update(100, 110);
// Predict 10% below: errors = (100-90)² = 100 each (same squared error)
theilU2.Update(100, 90);
theilU2.Update(100, 90);
// Both should produce valid bounded values
Assert.True(theilU1.Last.Value >= 0 && theilU1.Last.Value <= 1);
Assert.True(theilU2.Last.Value >= 0 && theilU2.Last.Value <= 1);
// The squared errors are the same, but denominators differ due to pred² terms
// So we just verify both produce sensible values (not exact equality)
Assert.True(double.IsFinite(theilU1.Last.Value));
Assert.True(double.IsFinite(theilU2.Last.Value));
}
}