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Differences Between: [Versions 310 and 311]

   1  <?php
   2  
   3  /**
   4   *
   5   * Function code for the complex log2() 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 base-2 logarithm of a complex number.
  14   *
  15   * @param     Complex|mixed    $complex    Complex number or a numeric value.
  16   * @return    Complex          The base-2 logarithm of the complex argument.
  17   * @throws    Exception        If argument isn't a valid real or complex number.
  18   * @throws    \InvalidArgumentException  If the real and the imaginary parts are both zero
  19   */
  20  function log2($complex)
  21  {
  22      $complex = Complex::validateComplexArgument($complex);
  23  
  24      if (($complex->getReal() == 0.0) && ($complex->getImaginary() == 0.0)) {
  25          throw new \InvalidArgumentException();
  26      } elseif (($complex->getReal() > 0.0) && ($complex->getImaginary() == 0.0)) {
  27          return new Complex(\log($complex->getReal(), 2), 0.0, $complex->getSuffix());
  28      }
  29  
  30      return ln($complex)
  31          ->multiply(\log(Complex::EULER, 2));
  32  }