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<?php |
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|
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/** |
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* |
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* Function code for the complex log2() function |
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* |
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* @copyright Copyright (c) 2013-2018 Mark Baker (https://github.com/MarkBaker/PHPComplex) |
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* @license https://opensource.org/licenses/MIT MIT |
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*/ |
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namespace Complex; |
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|
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/** |
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* Returns the base-2 logarithm of a complex number. |
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* |
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* @param Complex|mixed $complex Complex number or a numeric value. |
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* @return Complex The base-2 logarithm of the complex argument. |
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* @throws Exception If argument isn't a valid real or complex number. |
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* @throws \InvalidArgumentException If the real and the imaginary parts are both zero |
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*/ |
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function log2($complex) |
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{ |
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$complex = Complex::validateComplexArgument($complex); |
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|
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if (($complex->getReal() == 0.0) && ($complex->getImaginary() == 0.0)) { |
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throw new \InvalidArgumentException(); |
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} elseif (($complex->getReal() > 0.0) && ($complex->getImaginary() == 0.0)) { |
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return new Complex(\log($complex->getReal(), 2), 0.0, $complex->getSuffix()); |
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} |
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|
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return ln($complex) |
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->multiply(\log(Complex::EULER, 2)); |
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} |
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|
