Your IP : 192.168.165.1
<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* Linear values target.
*
* @package core_analytics
* @copyright 2017 David Monllao {@link http://www.davidmonllao.com}
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
namespace core_analytics\local\target;
defined('MOODLE_INTERNAL') || die();
/**
* Linear values target.
*
* @package core_analytics
* @copyright 2017 David Monllao {@link http://www.davidmonllao.com}
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
abstract class linear extends base {
/**
* Are the calculated values this target returns linear values?
*
* @return bool
*/
public function is_linear() {
// Not supported yet.
throw new \coding_exception('Sorry, this version\'s prediction processors only support targets with binary values.' .
' You can write your own and overwrite this method though.');
}
/**
* How positive is this calculated value?
*
* @param float $value
* @param string $ignoredsubtype
* @return int
*/
public function get_calculation_outcome($value, $ignoredsubtype = false) {
// This is very generic, targets will probably be interested in overwriting this.
$diff = static::get_max_value() - static::get_min_value();
if (($value - static::get_min_value()) / $diff >= 0.5) {
return self::OUTCOME_VERY_POSITIVE;
}
return self::OUTCOME_VERY_NEGATIVE;
}
/**
* Gets the maximum value for this target
*
* @return float
*/
public static function get_max_value() {
// Coding exception as this will only be called if this target have linear values.
throw new \coding_exception('Overwrite get_max_value() and return the target max value');
}
/**
* Gets the minimum value for this target
*
* @return float
*/
public static function get_min_value() {
// Coding exception as this will only be called if this target have linear values.
throw new \coding_exception('Overwrite get_min_value() and return the target min value');
}
/**
* This method determines if a prediction is interesing for the model or not.
*
* @param mixed $predictedvalue
* @param float $predictionscore
* @return bool
*/
public function triggers_callback($predictedvalue, $predictionscore) {
if (!parent::triggers_callback($predictedvalue, $predictionscore)) {
return false;
}
// People may not want to set a boundary.
$boundary = $this->get_callback_boundary();
if (!empty($boundary) && floatval($predictedvalue) < $boundary) {
return false;
}
return true;
}
/**
* Returns the minimum value that triggers the callback.
*
* @return float
*/
protected function get_callback_boundary() {
// Coding exception as this will only be called if this target have linear values.
throw new \coding_exception('Overwrite get_callback_boundary() and return the min value that ' .
'should trigger the callback');
}
}