public void ShouldExtrapolateTwoPeriodsBackwardAndTwoPeriodsForward()
{
int period = 24;
double[] data = new double[2 * period];
double dx = 2 * Math.PI / period;
for (int i = 0; i < data.Length; ++i)
{
int amplitude = 10 - i / period;
data[i] = amplitude * Math.Sin(i * dx);
}
double[] extendedData = new double[6 * period];
var sssmoother = new CyclicSubSeriesSmoother(7, 1, 1, data.Length, period, 2, 2);
sssmoother.Smooth(data, extendedData, null);
for (int i = 0; i < extendedData.Length; ++i)
{
int amplitude = 12 - i / period; // Two extra for the extrapolation before.
double value = amplitude * Math.Sin(i * dx);
Assert.AreEqual(extendedData[i], value, 1.0e-11, $"Test point {i}");
}
}
public void TrendingSinusoidExtrapolationTest()
{
int period = 24;
double[] data = new double[2 * period];
double dx = 2 * Math.PI / period;
for (int i = 0; i < data.Length; ++i)
{
int amplitude = 10 - i / period;
data[i] = amplitude * Math.Sin(i * dx);
}
double[] extendedData = new double[4 * period];
var sssmoother = new CyclicSubSeriesSmoother(7, 1, 1, data.Length, period, 1, 1);
sssmoother.Smooth(data, extendedData, null);
for (int i = 0; i < extendedData.Length; ++i)
{
int amplitude = 11 - i / period; // An extra for the extrapolation before.
double value = amplitude * Math.Sin(i * dx);
Assert.AreEqual(extendedData[i], value, 1.0e-11, $"Test point {i}");
}
}
