return pow( $mean - $x, 2 );
}, $this->points ) ) / ( count( $rstat ) - 1 );
$stddev = sqrt( $variance );
- $min = min( $this->points );
- $max = max( $this->points );
$this->assertEquals( count( $rstat ), count( $this->points ) );
$this->assertEquals( $rstat->min, min( $this->points ) );