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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 cos() 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 cosine of a complex number.
  14   *
  15   * @param     Complex|mixed    $complex    Complex number or a numeric value.
  16   * @return    Complex          The cosine of the complex argument.
  17   * @throws    Exception        If argument isn't a valid real or complex number.
  18   */
  19  function cos($complex): Complex
  20  {
  21      $complex = Complex::validateComplexArgument($complex);
  22  
  23      if ($complex->isReal()) {
  24          return new Complex(\cos($complex->getReal()));
  25      }
  26  
  27      return conjugate(
  28          new Complex(
  29              \cos($complex->getReal()) * \cosh($complex->getImaginary()),
  30              \sin($complex->getReal()) * \sinh($complex->getImaginary()),
  31              $complex->getSuffix()
  32          )
  33      );
  34  }