/// <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)); }