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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 tan() 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 tangent of a complex number. |
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* |
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* @param Complex|mixed $complex Complex number or a numeric value. |
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* @return Complex The tangent of the complex argument. |
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* @throws Exception If argument isn't a valid real or complex number. |
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* @throws \InvalidArgumentException If function would result in a division by zero |
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*/ |
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function tan($complex) |
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{ |
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$complex = Complex::validateComplexArgument($complex); |
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|
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if ($complex->isReal()) { |
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return new Complex(\tan($complex->getReal())); |
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} |
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|
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$real = $complex->getReal(); |
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$imaginary = $complex->getImaginary(); |
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$divisor = 1 + \pow(\tan($real), 2) * \pow(\tanh($imaginary), 2); |
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if ($divisor == 0.0) { |
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throw new \InvalidArgumentException('Division by zero'); |
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} |
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|
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return new Complex( |
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\pow(sech($imaginary)->getReal(), 2) * \tan($real) / $divisor, |
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\pow(sec($real)->getReal(), 2) * \tanh($imaginary) / $divisor, |
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$complex->getSuffix() |
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); |
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} |
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|
