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Differences Between: [Versions 310 and 311] [Versions 39 and 311]

   1  <?php
   2  
   3  /**
   4   *
   5   * Function code for the complex atanh() function
   6   *
   7   * @copyright  Copyright (c) 2013-2018 Mark Baker (https://github.com/MarkBaker/PHPComplex)
   8   * @license    https://opensource.org/licenses/MIT    MIT
   9   */
  10  namespace Complex;
  11  
  12  /**
  13   * Returns the inverse hyperbolic tangent of a complex number.
  14   *
  15   * @param     Complex|mixed    $complex    Complex number or a numeric value.
  16   * @return    Complex          The inverse hyperbolic tangent of the complex argument.
  17   * @throws    Exception        If argument isn't a valid real or complex number.
  18   */
  19  function atanh($complex): Complex
  20  {
  21      $complex = Complex::validateComplexArgument($complex);
  22  
  23      if ($complex->isReal()) {
  24          $real = $complex->getReal();
  25          if ($real >= -1.0 && $real <= 1.0) {
  26              return new Complex(\atanh($real));
  27          } else {
  28              return new Complex(\atanh(1 / $real), (($real < 0.0) ? M_PI_2 : -1 * M_PI_2));
  29          }
  30      }
  31  
  32      $iComplex = clone $complex;
  33      $iComplex = $iComplex->invertImaginary()
  34          ->reverse();
  35      return atan($iComplex)
  36          ->invertReal()
  37          ->reverse();
  38  }