tanh method
Implementation
MathComplex tanh(){
if( _im == 0.0 ){
return floatToComplex( ftanh( _re ) );
}
double re2 = _re * 2.0;
double im2 = _im * 2.0;
double d = fcosh( re2 ) + ClipMath.cos( im2 );
if( d == 0.0 ){
ClipMath.setComplexError();
}
return MathComplex(
fsinh( re2 ) / d,
ClipMath.sin( im2 ) / d
);
}