/// <summary>
/// Computes the cross-correlation of a finite and a enumerable signal.
/// </summary>
/// <param name="s1">The finite signal.</param>
/// <param name="s2">The enumerable signal.</param>
/// <returns></returns>
/// <exception cref="SamplerateMismatchException"></exception>
public static IEnumerableSignal CrossCorrelate(this IFiniteSignal s1, IEnumerableSignal s2)
{
if (s1.SampleRate != s2.SampleRate)
{
throw new SamplerateMismatchException();
}
return(new EnumerableSignal(Dsp.CrossCorrelate(s2.Signal, s1.Signal), s1.SampleRate, s1.Start - s2.Start)
{
DisplayName = "cross correlation"
});
}
public void TestCrossCorrelate2()
{
Fft.FftProvider = new FftwProvider();
var x = new[]
{
0.616044676146639,
0.473288848902729,
0.351659507062997,
0.830828627896291,
0.585264091152724,
0.549723608291140,
0.917193663829810,
0.285839018820374,
0.757200229110721,
0.753729094278495
};
var y = new[]
{
0.380445846975357,
0.567821640725221,
0.075854289563064,
0.053950118666607,
0.530797553008973,
0.779167230102011,
0.934010684229183,
0.129906208473730,
0.568823660872193,
0.469390641058206
};
var target = new[]
{
0.289165605456966,
0.572578144138708,
0.514311605265986,
1.226890899803151,
1.715053887382157,
1.723096881636733,
2.153707981735077,
2.180225109104805,
2.452308536614765,
2.991904576873709,
2.274857481454638,
2.194310061297180,
2.185291802257769,
1.609001416200661,
1.192553191608914,
0.609348760441016,
0.595874529034391,
0.716057373469512,
0.286753103662751
};
var result = Dsp.CrossCorrelate((IEnumerable <double>)x, y).ToReadOnlyList();
FilterAssert.ListsAreReasonablyClose(target, result);
Assert.That(Dsp.CrossCorrelate(Enumerable.Empty <double>(), y).ToReadOnlyList().Count == 0);
Assert.That(Dsp.CrossCorrelate((IEnumerable <double>)x, new List <double>()).ToReadOnlyList().Count == 0);
Assert.Throws <ArgumentNullException>(() => Dsp.CrossCorrelate((IEnumerable <double>)null, y).ToReadOnlyList());
Assert.Throws <ArgumentNullException>(() => Dsp.CrossCorrelate((IEnumerable <double>)x, null).ToReadOnlyList());
}