atanh Inverse hyperbolic tangent &reftitle.description; floatatanh floatarg Returns the inverse hyperbolic tangent of arg, i.e. the value whose hyperbolic tangent is arg. &reftitle.parameters; arg The argument to process &reftitle.returnvalues; Inverse hyperbolic tangent of arg &reftitle.changelog; &Version; &Description; 5.3.0 This function is now available on all platforms &reftitle.seealso; tanh atan asinh acosh