<?php

/**
 *
 * Function code for the complex acoth() function
 *
 * @copyright  Copyright (c) 2013-2018 Mark Baker (https://github.com/MarkBaker/PHPComplex)
 * @license    https://opensource.org/licenses/MIT    MIT
 */
namespace Complex;

/**
 * Returns the inverse hyperbolic cotangent of a complex number.
 *
 * @param     Complex|mixed    $complex    Complex number or a numeric value.
 * @return    Complex          The inverse hyperbolic cotangent of the complex argument.
 * @throws    Exception        If argument isn't a valid real or complex number.
 * @throws    \InvalidArgumentException    If function would result in a division by zero
 */

< function acoth($complex)



> function acoth($complex): Complex


{
    $complex = Complex::validateComplexArgument($complex);

    return atanh(inverse($complex));
}