Files
QuanTAlib/lib/errors/rsquared/Rsquared.Tests.cs
T
2026-02-10 21:33:16 -08:00

407 lines
13 KiB
C#

namespace QuanTAlib.Tests;
public class RsquaredTests
{
private readonly GBM _gbm;
private const int Period = 10;
public RsquaredTests()
{
_gbm = new GBM(startPrice: 100, mu: 0.05, sigma: 0.2, seed: 42);
}
[Fact]
public void Constructor_ValidatesInput()
{
Assert.Throws<ArgumentException>(() => new Rsquared(0));
Assert.Throws<ArgumentException>(() => new Rsquared(-1));
var r2 = new Rsquared(10);
Assert.NotNull(r2);
}
[Fact]
public void Calc_ReturnsValue()
{
var r2 = new Rsquared(Period);
var time = DateTime.UtcNow;
var result = r2.Update(new TValue(time, 100), new TValue(time, 95));
Assert.True(result.Value <= 1.0);
Assert.Equal(result.Value, r2.Last.Value);
}
[Fact]
public void Properties_Accessible()
{
var r2 = new Rsquared(Period);
Assert.Equal(0, r2.Last.Value);
Assert.False(r2.IsHot);
Assert.Contains("R²", r2.Name, StringComparison.Ordinal);
r2.Update(new TValue(DateTime.UtcNow, 100), new TValue(DateTime.UtcNow, 95));
Assert.NotEqual(0, r2.Last.Value);
}
[Fact]
public void Calc_IsNew_AcceptsParameter()
{
var r2 = new Rsquared(Period);
var time = DateTime.UtcNow;
r2.Update(new TValue(time, 100), new TValue(time, 95), isNew: true);
double value1 = r2.Last.Value;
r2.Update(new TValue(time.AddSeconds(1), 102), new TValue(time.AddSeconds(1), 98), isNew: true);
double value2 = r2.Last.Value;
Assert.NotEqual(value1, value2);
}
[Fact]
public void Calc_IsNew_False_UpdatesValue()
{
var r2 = new Rsquared(Period);
var time = DateTime.UtcNow;
r2.Update(new TValue(time, 100), new TValue(time, 95));
r2.Update(new TValue(time.AddSeconds(1), 105), new TValue(time.AddSeconds(1), 100), isNew: true);
double beforeUpdate = r2.Last.Value;
r2.Update(new TValue(time.AddSeconds(1), 110), new TValue(time.AddSeconds(1), 100), isNew: false);
double afterUpdate = r2.Last.Value;
Assert.NotEqual(beforeUpdate, afterUpdate);
}
[Fact]
public void Reset_ClearsState()
{
var r2 = new Rsquared(Period);
r2.Update(new TValue(DateTime.UtcNow, 100), new TValue(DateTime.UtcNow, 95));
r2.Update(new TValue(DateTime.UtcNow, 105), new TValue(DateTime.UtcNow, 100));
r2.Reset();
Assert.Equal(0, r2.Last.Value);
Assert.False(r2.IsHot);
r2.Update(new TValue(DateTime.UtcNow, 50), new TValue(DateTime.UtcNow, 48));
Assert.NotEqual(0, r2.Last.Value);
}
[Fact]
public void IsHot_BecomesTrueWhenBufferFull()
{
var r2 = new Rsquared(5);
Assert.False(r2.IsHot);
for (int i = 1; i <= 4; i++)
{
r2.Update(new TValue(DateTime.UtcNow, 100 + i), new TValue(DateTime.UtcNow, 100));
Assert.False(r2.IsHot);
}
r2.Update(new TValue(DateTime.UtcNow, 106), new TValue(DateTime.UtcNow, 101));
Assert.True(r2.IsHot);
}
[Fact]
public void NaN_Input_UsesLastValidValue()
{
var r2 = new Rsquared(Period);
r2.Update(new TValue(DateTime.UtcNow, 100), new TValue(DateTime.UtcNow, 95));
r2.Update(new TValue(DateTime.UtcNow, 105), new TValue(DateTime.UtcNow, 100));
var resultAfterNaN = r2.Update(new TValue(DateTime.UtcNow, double.NaN), new TValue(DateTime.UtcNow, 102));
Assert.True(double.IsFinite(resultAfterNaN.Value));
}
[Fact]
public void Infinity_Input_UsesLastValidValue()
{
var r2 = new Rsquared(Period);
r2.Update(new TValue(DateTime.UtcNow, 100), new TValue(DateTime.UtcNow, 95));
r2.Update(new TValue(DateTime.UtcNow, 105), new TValue(DateTime.UtcNow, 100));
var resultAfterPosInf = r2.Update(new TValue(DateTime.UtcNow, double.PositiveInfinity), new TValue(DateTime.UtcNow, 102));
Assert.True(double.IsFinite(resultAfterPosInf.Value));
var resultAfterNegInf = r2.Update(new TValue(DateTime.UtcNow, 108), new TValue(DateTime.UtcNow, double.NegativeInfinity));
Assert.True(double.IsFinite(resultAfterNegInf.Value));
}
[Fact]
public void PerfectPrediction_ReturnsOne()
{
var r2 = new Rsquared(Period);
var time = DateTime.UtcNow;
// Different actual values but perfect predictions
for (int i = 0; i < 20; i++)
{
double val = 100 + i * 2;
r2.Update(new TValue(time.AddSeconds(i), val), new TValue(time.AddSeconds(i), val));
}
Assert.Equal(1.0, r2.Last.Value, 1e-10);
}
[Fact]
public void R2EqualsOneMinusRse()
{
// R² = 1 - RSE relationship
var r2 = new Rsquared(10);
var rse = new Rse(10);
var time = DateTime.UtcNow;
// Generate data with some error
for (int i = 0; i < 20; i++)
{
double actual = 100 + i * 2;
double predicted = actual + (i % 3 - 1) * 2;
r2.Update(new TValue(time.AddSeconds(i), actual), new TValue(time.AddSeconds(i), predicted));
rse.Update(new TValue(time.AddSeconds(i), actual), new TValue(time.AddSeconds(i), predicted));
}
double r2Value = r2.Last.Value;
double rseValue = rse.Last.Value;
// R² = 1 - RSE
Assert.Equal(r2Value, 1.0 - rseValue, 1e-10);
}
[Fact]
public void MeanPredictor_ReturnsApproximatelyZero()
{
// When prediction = mean of actuals, R² ≈ 0
var r2 = new Rsquared(5);
var time = DateTime.UtcNow;
double[] values = { 100, 104, 96, 108, 92, 110, 90, 105, 95, 100 };
// Use running mean as predictor
double runningSum = 0;
for (int i = 0; i < values.Length; i++)
{
runningSum += values[i];
double mean = runningSum / (i + 1);
r2.Update(new TValue(time.AddSeconds(i), values[i]), new TValue(time.AddSeconds(i), mean));
}
// R² should be close to 0 when predicting the mean
Assert.True(r2.Last.Value > -0.5 && r2.Last.Value < 0.5,
$"Expected R² ≈ 0, got {r2.Last.Value}");
}
[Fact]
public void GoodPredictions_HighR2()
{
var r2 = new Rsquared(10);
var time = DateTime.UtcNow;
// Linear trend with small random noise in predictions
for (int i = 0; i < 20; i++)
{
double actual = 100 + i * 2;
double predicted = actual + (i % 2 == 0 ? 0.5 : -0.5); // Small systematic error
r2.Update(new TValue(time.AddSeconds(i), actual), new TValue(time.AddSeconds(i), predicted));
}
// Good predictions should have high R²
Assert.True(r2.Last.Value > 0.9, $"Expected R² > 0.9 for good predictions, got {r2.Last.Value}");
}
[Fact]
public void NegativeR2_WorseThanMean()
{
var r2 = new Rsquared(10);
var time = DateTime.UtcNow;
// Predictions that are anti-correlated with actuals
for (int i = 0; i < 20; i++)
{
double actual = 100 + (i % 2 == 0 ? 10 : -10);
double predicted = 100 + (i % 2 == 0 ? -10 : 10); // Opposite direction
r2.Update(new TValue(time.AddSeconds(i), actual), new TValue(time.AddSeconds(i), predicted));
}
// Anti-correlated predictions should have negative R²
Assert.True(r2.Last.Value < 0, $"Expected R² < 0 for anti-correlated predictions, got {r2.Last.Value}");
}
[Fact]
public void FlatLine_ReturnsOne()
{
var r2 = new Rsquared(Period);
// Flat actual values means TSS = 0
// Should return 1.0 (default when TSS is zero)
for (int i = 0; i < 20; i++)
{
r2.Update(new TValue(DateTime.UtcNow, 100), new TValue(DateTime.UtcNow, 95));
}
// When all actual values are the same, TSS = 0, returns 1.0
Assert.Equal(1.0, r2.Last.Value, 1e-10);
}
[Fact]
public void R2_RangeUpperBoundIsOne()
{
var r2 = new Rsquared(Period);
var time = DateTime.UtcNow;
for (int i = 0; i < 100; i++)
{
double actual = 100 + Math.Sin(i * 0.1) * 20;
double predicted = actual + (i % 5 - 2); // Small systematic error
r2.Update(new TValue(time.AddSeconds(i), actual), new TValue(time.AddSeconds(i), predicted));
// R² should never exceed 1
Assert.True(r2.Last.Value <= 1.0 + 1e-10,
$"R² = {r2.Last.Value} exceeded 1.0 at iteration {i}");
}
}
[Fact]
public void BatchCalc_MatchesIterativeCalc()
{
var r2Iterative = new Rsquared(Period);
var bars = _gbm.Fetch(100, DateTime.UtcNow.Ticks, TimeSpan.FromMinutes(1));
var actual = bars.Close;
var predicted = new TSeries();
foreach (var item in actual)
{
predicted.Add(item.Time, item.Value * 0.98);
}
var iterativeResults = new List<double>();
for (int i = 0; i < actual.Count; i++)
{
iterativeResults.Add(r2Iterative.Update(actual[i], predicted[i]).Value);
}
var batchResults = Rsquared.Batch(actual, predicted, Period);
Assert.Equal(iterativeResults.Count, batchResults.Count);
for (int i = 0; i < iterativeResults.Count; i++)
{
Assert.Equal(iterativeResults[i], batchResults[i].Value, 1e-9);
}
}
[Fact]
public void SpanBatch_ValidatesInput()
{
double[] actual = [1, 2, 3, 4, 5];
double[] predicted = [1, 2, 3, 4, 5];
double[] output = new double[5];
double[] wrongSizeOutput = new double[3];
Assert.Throws<ArgumentException>(() =>
Rsquared.Batch(actual.AsSpan(), predicted.AsSpan(), output.AsSpan(), 0));
Assert.Throws<ArgumentException>(() =>
Rsquared.Batch(actual.AsSpan(), predicted.AsSpan(), output.AsSpan(), -1));
Assert.Throws<ArgumentException>(() =>
Rsquared.Batch(actual.AsSpan(), predicted.AsSpan(), wrongSizeOutput.AsSpan(), 3));
}
[Fact]
public void SpanBatch_MatchesTSeriesBatch()
{
var bars = _gbm.Fetch(100, DateTime.UtcNow.Ticks, TimeSpan.FromMinutes(1));
var actualSeries = bars.Close;
var predictedSeries = new TSeries();
foreach (var item in actualSeries)
{
predictedSeries.Add(item.Time, item.Value * 0.98);
}
double[] actualArr = actualSeries.Values.ToArray();
double[] predictedArr = predictedSeries.Values.ToArray();
double[] output = new double[100];
var tseriesResult = Rsquared.Batch(actualSeries, predictedSeries, Period);
Rsquared.Batch(actualArr.AsSpan(), predictedArr.AsSpan(), output.AsSpan(), Period);
for (int i = 0; i < 100; i++)
{
Assert.Equal(tseriesResult[i].Value, output[i], 1e-10);
}
}
[Fact]
public void AllModes_ProduceSameResult()
{
var bars = _gbm.Fetch(100, DateTime.UtcNow.Ticks, TimeSpan.FromMinutes(1));
var actualSeries = bars.Close;
var predictedSeries = new TSeries();
foreach (var item in actualSeries)
{
predictedSeries.Add(item.Time, item.Value * 0.98);
}
// 1. Batch Mode (static method)
var batchSeries = Rsquared.Batch(actualSeries, predictedSeries, Period);
double expected = batchSeries.Last.Value;
// 2. Span Mode
double[] actualArr = actualSeries.Values.ToArray();
double[] predictedArr = predictedSeries.Values.ToArray();
double[] spanOutput = new double[actualArr.Length];
Rsquared.Batch(actualArr.AsSpan(), predictedArr.AsSpan(), spanOutput.AsSpan(), Period);
double spanResult = spanOutput[^1];
// 3. Streaming Mode
var streamingInd = new Rsquared(Period);
for (int i = 0; i < actualSeries.Count; i++)
{
streamingInd.Update(actualSeries[i], predictedSeries[i]);
}
double streamingResult = streamingInd.Last.Value;
Assert.Equal(expected, spanResult, precision: 9);
Assert.Equal(expected, streamingResult, precision: 9);
}
[Fact]
public void DoubleOverload_Works()
{
var r2 = new Rsquared(Period);
var result = r2.Update(100.0, 95.0);
Assert.True(result.Value <= 1.0);
Assert.Equal(result.Value, r2.Last.Value);
}
[Fact]
public void SingleInputUpdate_Throws()
{
var r2 = new Rsquared(Period);
Assert.Throws<NotSupportedException>(() =>
r2.Update(new TValue(DateTime.UtcNow, 100)));
}
[Fact]
public void SingleInputTSeriesUpdate_Throws()
{
var r2 = new Rsquared(Period);
var series = new TSeries();
series.Add(DateTime.UtcNow, 100);
Assert.Throws<NotSupportedException>(() => r2.Update(series));
}
}