コード例 #1
0
ファイル: ArrayList.php プロジェクト: dazarobbo/cola
 /**
  * Computes the population standard deviation for the numbers
  * in this list
  * @return string
  */
 public function stdDev()
 {
     Number::setScale(static::NUMERIC_FUNCTIONS_SCALE);
     $mean = $this->average();
     $squares = new static();
     foreach ($this->_Arr as $num) {
         $squares->add(Number::pow(Number::sub(\strval($num), $mean), '2'));
     }
     return Number::sqrt($squares->average());
 }
コード例 #2
0
 public function testSqrt()
 {
     $n = '121';
     $exp = '11';
     $this->assertEquals($exp, Number::sqrt($n));
 }