public function median()
    {
        if ($this->n < 1) {
            throw new RuntimeException('Median is not defined for vectors'
                . ' with less than 1 element.');
        }

        $mid = intdiv($this->n, 2);

        $a = $this->a;

        sort($a);

        if ($this->n % 2 === 1) {
            $median = $a[$mid];
        } else {
            $median = ($a[$mid - 1] + $a[$mid]) / 2.;
        }

        return $median;
    }
public function median()
    {
        if ($this->n < 1) {
            throw new RuntimeException('Median is not defined for vectors'
                . ' with less than 1 element.');
        }

        $mid = intdiv($this->n, 2);

        $a = $this->a;

        sort($a);

        if ($this->n % 2 === 1) {
            $median = $a[$mid];
        } else {
            $median = ($a[$mid - 1] + $a[$mid]) / 2.;
        }

        return $median;
    }
public function median ( ) { if ( $ this -> n < 1 ) { throw new RuntimeException ( 'Median is not defined for vectors' . ' with less than 1 element.' ) ; } $ mid = intdiv ( $ this -> n , 2 ) ; $ a = $ this -> a ; sort ( $ a ) ; if ( $ this -> n % 2 === 1 ) { $ median = $ a [ $ mid ] ; } else { $ median = ( $ a [ $ mid - 1 ] + $ a [ $ mid ] ) / 2. ; } return $ median ; }
Return the median of the vector.

@throws \RuntimeException
@return int|float
Return the median of the vector .