internal override Symbol PreEval(Symbol x)
{
var z = x.ToComplex();
if (z.Re < 0 || z.Im != 0.0)
{
return(new Complex(Math.log(z.Re * z.Re + z.Im * z.Im) / 2, Math.atan2(z.Im, z.Re)));
}
return(new Complex(Math.log(z.Re)));
}
internal override Algebraic SymEval(Algebraic x, Algebraic y)
{
if (y is Complex && !y.IsComplex() && x is Complex && !x.IsComplex())
{
return(new Complex(Math.atan2((( Complex )y).Re, (( Complex )x).Re)));
}
if (Symbol.ZERO != x)
{
return(FunctionVariable.Create("atan", y / x) + FunctionVariable.Create("sign", y) * (Symbol.ONE - FunctionVariable.Create("sign", x)) * Symbol.PI / Symbol.TWO);
}
else
{
return((FunctionVariable.Create("sign", y) * Symbol.PI) / Symbol.TWO);
}
}
public virtual Complex Arg()
{
return(new Complex(Math.atan2(Im, Re)));
}
