32 lines
495 B
PHP
32 lines
495 B
PHP
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<?php
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/**
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* Pythagorean Theorem:.
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*
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* a = 3
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* b = 4
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* r = sqrt(square(a) + square(b))
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* r = 5
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*
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* r = sqrt(a^2 + b^2) without under/overflow.
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*
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* @param mixed $a
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* @param mixed $b
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*
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* @return float
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*/
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function hypo($a, $b)
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{
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if (abs($a) > abs($b)) {
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$r = $b / $a;
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$r = abs($a) * sqrt(1 + $r * $r);
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} elseif ($b != 0) {
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$r = $a / $b;
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$r = abs($b) * sqrt(1 + $r * $r);
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} else {
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$r = 0.0;
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}
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return $r;
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}
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