public function getReading($side, $method)
{
if (!$this->_readings_by_method) {
$this->_readings_by_method = array();
foreach (array('left', 'right') as $side) {
$this->_readings_by_method[$side] = array();
foreach ($this->{$side . '_readings'} as $reading) {
$this->_readings_by_method[$side][$reading->method_id] = $reading;
}
}
}
return @$this->_readings_by_method[$side][$method->id];
}