public void CreationTest()
{
const double fd = 1000;
const double dt = 1 / fd;
const double f0 = 30;
const double delta_f = 10;
var w = Tan(PI * f0 * dt);
const double dw = PI * delta_f * dt;
var expected_b0 = w * w + 1;
var expected_b1 = 2 * (w * w - 1);
var expected_b2 = w * w + 1;
var expected_a0 = w * w + dw + 1;
var expected_a1 = 2 * (w * w - 1);
var expected_a2 = w * w - dw + 1;
var rlc = new BandStopRLC(f0, delta_f, dt);
var a = rlc.A;
var b = rlc.B;
Assert.AreEqual(expected_b0, b[0]);
Assert.AreEqual(expected_b1, b[1]);
Assert.AreEqual(expected_b2, b[2]);
Assert.AreEqual(expected_a0, a[0]);
Assert.AreEqual(expected_a1, a[1]);
Assert.AreEqual(expected_a2, a[2]);
}
public void TransmissionCoefficientAtZeroFrequencyTestTest()
{
const double fd = 1000;
const double dt = 1 / fd;
const double f0 = 30;
const double delta_f = 10;
var rlc = new BandStopRLC(f0, delta_f, dt);
var c = rlc.GetTransmissionCoefficient(0, dt);
Assert.AreEqual(1, c.Abs, $"delta:{Abs(1 - c.Abs):e2}");
}
public void TransmissionCoefficientAtCentralFrequencyTestTest()
{
const double fd = 1000;
const double dt = 1 / fd;
const double f0 = 30;
const double delta_f = 10;
var rlc = new BandStopRLC(f0, delta_f, dt);
var c = rlc.GetTransmissionCoefficient(f0, dt);
const double eps = 1.91e-14;
Assert.AreEqual(0, c.Abs, eps, $"delta:{Abs(0 - c.Abs):e2}");
}
public void ProcessSignalAtHighFrequencyTestTest()
{
const double fd = 1000;
const double dt = 1 / fd;
const double f0 = 30;
const double delta_f = 10;
const double eps = 2.31e-5;
var x0 = new SamplesDigitalSignal(dt, 1024, t => 1 * Cos(2 * PI * fd / 2 * t));
var x0_power = x0.Power;
Assert.AreEqual(1, x0_power, eps);
var rlc = new BandStopRLC(f0, delta_f, dt);
var y0 = rlc.Process(x0);
var y0_power = y0.Power;
Assert.AreEqual(x0_power, y0_power, eps, $"delta:{Abs(x0_power - y0_power):e2}");
}
public void ProcessSignalAtCentralFrequencyTestTest()
{
const double fd = 1000;
const double dt = 1 / fd;
const double f0 = 30;
const double delta_f = 10;
const double eps = 0.048;
const double A0 = Consts.sqrt_2;
var x0 = new SamplesDigitalSignal(dt, 1024, t => A0 * Cos(2 * PI * f0 * t));
var x0_power = x0.Power;
Assert.AreEqual(1, x0_power, eps);
var rlc = new BandStopRLC(f0, delta_f, dt);
var y0 = rlc.Process(x0);
var y0_power = y0.Power;
Assert.AreEqual(0, y0_power, eps, $"delta:{Abs(0 - y0_power)}");
}
public void ImpulseResponseTest()
{
const double fd = 1000;
const double dt = 1 / fd;
const double f0 = 30;
const double delta_f = 10;
var rlc = new BandStopRLC(f0, delta_f, dt);
var a = rlc.A;
var b = rlc.B;
var a0 = a[0];
var a1 = a[1] / a0;
var a2 = a[2] / a0;
var b0 = b[0] / a0;
var b1 = b[1] / a0;
var b2 = b[2] / a0;
var expected_impulse_response = new List <double>
{
b0,
b0 * -a1 + b1,
b0 *(-a1 * -a1 + -a2) + b1 * -a1 + b2,
b0 *(-a1 * -a2 + -a1 * (-a1 * -a1 + -a2)) + b1 * (-a1 * -a1 + -a2) + b2 * -a1
};
var delta = new double[expected_impulse_response.Count];
delta[0] = 1;
var impulse_response = rlc.Process(delta).ToArray();
const double eps = 5.6e-16;
CollectionAssert.AreEqual(expected_impulse_response, impulse_response, GetComparer(eps));
}
