src/Malenki/Math/Stats/NormalDistribution.php
public function fn(array &$arr_x)
    {
        $arr = array();

        foreach ($arr_x as $x) {
            $item = new \stdClass();
            $item->x = $x;
            $item->fx = $this->f($x);
            $arr[] = $item;
        }

        return $arr;
    }
public function fn(array &$arr_x)
    {
        $arr = array();

        foreach ($arr_x as $x) {
            $item = new \stdClass();
            $item->x = $x;
            $item->fx = $this->f($x);
            $arr[] = $item;
        }

        return $arr;
    }
Do same things like NormalDistribution::f() but for several values at once.

@see NormalDistribution::precision()
@param  array $arr_x Several x values
@access public
@return array Each items is small object having x and fx attributes.