public void CrossValidationUtilities_GetKFoldCrossValidationIndexSets_Indices()
{
var targets = new double[] { 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3 };
var indices = new int[] { 0, 1, 2, 3, 4, 5, 6 };
var sampler = new StratifiedIndexSampler <double>(seed: 242);
var actuals = CrossValidationUtilities.GetKFoldCrossValidationIndexSets(sampler,
foldCount: 2, targets: targets, indices: indices);
TraceIndexSets(actuals);
var expecteds = new List <(int[] trainingIndices, int[] validationIndices)>
{
// Sets contains values from the indices array only.
(new int[] { 1, 3, 4, 5 }, new int[] { 2, 6, 0 }),
(new int[] { 0, 2, 6 }, new int[] { 1, 3, 4, 5 }),
};
Assert.AreEqual(expecteds.Count, actuals.Count);
for (int i = 0; i < expecteds.Count; i++)
{
var expected = expecteds[i];
var actual = actuals[i];
CollectionAssert.AreEqual(expected.trainingIndices, actual.trainingIndices);
CollectionAssert.AreEqual(expected.validationIndices, actual.validationIndices);
}
}
public void CrossValidationUtilities_GetKFoldCrossValidationIndexSets_Handle_Remainder()
{
var targets = new double[] { 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3 };
var sampler = new StratifiedIndexSampler <double>(seed: 242);
var actuals = CrossValidationUtilities.GetKFoldCrossValidationIndexSets(sampler,
foldCount: 4, targets: targets);
var expecteds = new List <(int[] trainingIndices, int[] validationIndices)>
{
(new int[] { 0, 1, 2, 3, 5, 6, 7, 9, 11, 12, 13, 14 }, new int[] { 10, 4, 8 }),
(new int[] { 0, 1, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13 }, new int[] { 2, 7, 14 }),
(new int[] { 1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 14 }, new int[] { 5, 13, 0 }),
// Handle remainder from target.length / foldsCount,
// by adding remaining indices to the last set
(new int[] { 0, 2, 4, 5, 7, 8, 10, 13, 14 }, new int[] { 1, 3, 6, 9, 11, 12 }),
};
Assert.AreEqual(expecteds.Count, actuals.Count);
for (int i = 0; i < expecteds.Count; i++)
{
var expected = expecteds[i];
var actual = actuals[i];
CollectionAssert.AreEqual(expected.trainingIndices, actual.trainingIndices);
CollectionAssert.AreEqual(expected.validationIndices, actual.validationIndices);
}
}
public void CrossValidationUtilities_GetKFoldCrossValidationIndexSets()
{
var targets = new double[] { 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3 };
var sampler = new StratifiedIndexSampler <double>(seed: 242);
var actuals = CrossValidationUtilities.GetKFoldCrossValidationIndexSets(sampler,
foldCount: 4, targets: targets);
TraceIndexSets(actuals);
var expecteds = new List <(int[] trainingIndices, int[] validationIndices)>
{
(new int[] { 0, 1, 3, 4, 5, 7, 9, 10, 11 }, new int[] { 6, 8, 2 }),
(new int[] { 0, 2, 3, 4, 6, 7, 8, 9, 10 }, new int[] { 1, 11, 5 }),
(new int[] { 0, 1, 2, 4, 5, 6, 8, 9, 11 }, new int[] { 7, 3, 10 }),
(new int[] { 1, 2, 3, 5, 6, 7, 8, 10, 11 }, new int[] { 0, 4, 9 }),
};
Assert.AreEqual(expecteds.Count, actuals.Count);
for (int i = 0; i < expecteds.Count; i++)
{
var expected = expecteds[i];
var actual = actuals[i];
CollectionAssert.AreEqual(expected.trainingIndices, actual.trainingIndices);
CollectionAssert.AreEqual(expected.validationIndices, actual.validationIndices);
}
}
