public void EllipticFTest()
{
var z = new[] {
new Complex(-0.670791254938757, -0.0938159212065481),
new Complex(0.528053930350357, -1.07956370130938),
new Complex(-0.557287707188084, -1.00272777341254),
new Complex(0.320745728918526, 0.287620039090474),
new Complex(-0.420904792797892, 0.642254696882941),
new Complex(0.109863468987495, -0.47809418429494),
new Complex(-0.272688296113657, 0.197822903078282),
new Complex(10.9863468987495, -0.47809418429494),
new Complex(-27.2688296113657, 0.197822903078282),
};
var expected = new[] {
new Complex(-0.68620842267039771730, -0.10047616775855015460),
new Complex(0.42868733998557565682, -1.05995343584072013101),
new Complex(-0.46942504702869457356, -1.00008738595868835155),
new Complex(0.31819382130927205251, 0.29124965412479359813),
new Complex(-0.39580478305810881056, 0.64709397408138872245),
new Complex(0.10569294199103250250, -0.47295612599211204389),
new Complex(-0.27204914758137346116, 0.19984298803088524405),
new Complex(12.12391310952531579389, -0.5977215792388405620),
new Complex(-30.1535374477487750443, 0.22663693321479046126),
};
for (int i = 0; i < expected.Length; i++)
{
Complex f;
f = Elliptic.F(z[i], 0.333);
var err = (f - expected[i]).Magnitude;
Assert.IsTrue(err < 1e-14);
}
}
public void EllipticFLargeArgumentTest()
{
var x = 1436.699529559065124036301546242965863291805609504612854879;
var f = Elliptic.F(1000, .8);
Assert.IsTrue(Math.Abs(x - f) < 1e-12);
f = Elliptic.FDouble(.8)(1000);
Assert.IsTrue(Math.Abs(x - f) < 1e-12);
}
public void EllipticFModulusOneHalfTest()
{
double f;
var e = Elliptic.FDouble(Math.Sqrt(0.5));
f = Elliptic.F(.5, Math.Sqrt(0.5));
Assert.IsTrue(Math.Abs(f - 0.51516665702885808770) < 1e-12);
f = e(0);
Assert.AreEqual(0, f);
f = e(1);
Assert.IsTrue(Math.Abs(f - 1.1310061601574670032) < 1e-12);
}
public void EllipticFMatchesComplexTest()
{
var rand = new Random("EllipticFMatchesComplexTest".GetHashCode());
for (int i = 0; i < 100; i++)
{
var m = rand.NextDouble();
var efm = Elliptic.FComplex(m);
var z = RandomZ(rand);
var f1 = Elliptic.F(z, m);
var f2 = efm(z);
Assert.AreEqual(f1, f2);
}
}
public void EllipticFMatchesDoubleTest()
{
var rand = new Random("EllipticFMatchesDoubleTest".GetHashCode());
for (int i = 0; i < 100; i++)
{
var m = rand.NextDouble();
var efm = Elliptic.FDouble(m);
var x = Math.Sqrt(-2 * Math.Log(rand.NextDouble())) * Math.Cos(Math.PI * rand.NextDouble());
var f1 = Elliptic.F(x, m);
var f2 = efm(x);
Assert.AreEqual(f1, f2);
}
}
public override void GetAnalogPrototype(Coefficient[] coefs)
// public void GetAnalogPrototype2(Coefficient[] coefs)
{
double m1 = this.m1;
double m1p = 1 - this.m1;
double Kk1 = Elliptic.K(m1);
double Kk1p = Elliptic.K(m1p);
double m = Elliptic.InverseQ(Math.Exp(-Math.PI * Kk1p / (this.order * Kk1)));
double mp = 1 - m;
double Kk = Elliptic.K(m);
double phi, sn_p, cn_p, dn_p;
double v = Elliptic.F(Math.Atan(1 / this.epsilon), m1p) * Kk / (this.order * Kk1);
Elliptic.Jacobi(v, mp, out phi, out sn_p, out cn_p, out dn_p);
for (int i = this.order - 1, j = 0; i > 0; i -= 2, ++j)
{
Coefficient coef = coefs[j];
double sn, cn, dn;
double u = Kk * (double)i / this.order;
Elliptic.Jacobi(u, m, out phi, out sn, out cn, out dn);
double denom = 1 - dn * dn * sn_p * sn_p;
double re = -cn * dn * sn_p * cn_p / denom;
double im = -sn * dn_p / denom;
double alpha = -2 * re;
double beta = re * re + im * im;
double gamma = 1 / (m * sn * sn);
coef.a[0] = 1; coef.a[1] = alpha / beta; coef.a[2] = 1 / beta;
coef.b[0] = 1; coef.b[1] = 0; coef.b[2] = 1 / gamma;
}
if ((this.order & 1) == 1)
{
Coefficient coef = coefs[this.order / 2];
double denom = 1 - sn_p * sn_p;
double re = -sn_p * cn_p / denom;
coef.a[0] = 1; coef.a[1] = -1 / re; coef.a[2] = 0;
coef.b[0] = 1; coef.b[1] = 0; coef.b[2] = 0;
}
}
/// <summary>
/// フィルタの零点/極を計算。
/// </summary>
/// <param name="roots">零点/極一覧の格納先</param>
public override void GetZeroPole(ZeroPole[] roots)
{
double m1 = this.m1;
double m1p = 1 - this.m1;
double Kk1 = Elliptic.K(m1);
double Kk1p = Elliptic.K(m1p);
double temp1 = -Math.PI * Kk1p / (this.order * Kk1);
double temp2 = Math.Exp(temp1);
double m = Elliptic.InverseQ(Math.Exp(-Math.PI * Kk1p / (this.order * Kk1)));
double mp = 1 - m;
double k = Math.Sqrt(m);
double Kk = Elliptic.K(m);
double Kkp = Elliptic.K(mp);
double temp3 = (Kk / Kkp) / (Kk1 / Kk1p);
double phi, sn_p, cn_p, dn_p;
double v = Elliptic.F(Math.Atan(1 / this.epsilon), m1p) * Kk / (this.order * Kk1);
Elliptic.Jacobi(v, mp, out phi, out sn_p, out cn_p, out dn_p);
for (int i = this.order - 1, j = 0; i > 0; i -= 2, ++j)
{
double sn, cn, dn;
double u = Kk * (double)i / this.order;
Elliptic.Jacobi(u, m, out phi, out sn, out cn, out dn);
double denom = 1 - dn * dn * sn_p * sn_p;
double re = -cn * dn * sn_p * cn_p / denom;
double im = -sn * dn_p / denom;
roots[j].zero = new Root(Root.Type.Complex, 0, 1 / (k * sn));
roots[j].pole = new Root(Root.Type.Complex, re, im);
}
if ((this.order & 1) == 1)
{
double denom = 1 - sn_p * sn_p;
double re = -sn_p * cn_p / denom;
roots[this.order / 2].zero = new Root(Root.Type.None, 0, 0);
roots[this.order / 2].pole = new Root(Root.Type.Single, re, 0);
}
}