Softmax calculation for PHP (useful for logistic classifications)

softmax.php

function softmax(array $v){

    //Just in case values are passed in as string, apply floatval
    $v = array_map('exp',array_map('floatval',$v));
    $sum = array_sum($v);

    foreach($v as $index => $value) {
        $v[$index] = $value/$sum;
    }

    return $v;
}

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