/// <summary>Trigonometric Secant (sec, Sekans) of this <c>Complex</c>.</summary>
public Complex Secant()
{
if (IsReal)
{
return(new Complex(Trig.Secant(real), 0d));
}
double cosr = Trig.Cosine(real);
double sinhi = Trig.HyperbolicSine(imag);
double denom = cosr * cosr + sinhi * sinhi;
return(new Complex(cosr * Trig.HyperbolicCosine(imag) / denom, Trig.Sine(real) * sinhi / denom));
}
