Proyectos de Subversion Moodle

<?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/>.

/**

 * Multi-class classifier target.

 *

 * @package   core_analytics

 * @copyright 2019 Apetrei Vlad

 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

defined('MOODLE_INTERNAL') || die();

/**

 * Multi-class classifier target.

 *

 * @package   core_analytics

 * @copyright 2019 Apetrei Vlad

 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class test_target_shortname_multiclass extends \core_analytics\local\target\discrete {

    /**

     * Returns a lang_string object representing the name for the indicator.

     *

     * Used as column identificator.

     *

     * If there is a corresponding '_help' string this will be shown as well.

     *

     * @return \lang_string

     */

    public static function get_name(): \lang_string {

        // Using a string that exists and contains a corresponding '_help' string.

        return new \lang_string('allowstealthmodules');

    }

    /**

     * predictions

     *

     * @var array

     */

    protected $predictions = array();

    /**

     * is_linear

     *

     * @return bool

     */

    public function is_linear() {

        return false;

    }

    /**

     * Returns the target discrete values.

     *

     * Only useful for targets using discrete values, must be overwriten if it is the case.

     *

     * @return array

     */

    final public static function get_classes() {

        return array(0, 1, 2);

    }

    /**

     * Is the calculated value a positive outcome of this target?

     *

     * @param string $value

     * @param string $ignoredsubtype

     * @return int

     */

    public function get_calculation_outcome($value, $ignoredsubtype = false) {

        if (!self::is_a_class($value)) {

            throw new \moodle_exception('errorpredictionformat', 'analytics');

        }

        if (in_array($value, $this->ignored_predicted_classes(), false)) {

            // Just in case, if it is ignored the prediction should not even be recorded but if it would, it is ignored now,

            // which should mean that is it nothing serious.

            return self::OUTCOME_VERY_POSITIVE;

        }

        // By default binaries are danger when prediction = 1.

        if ($value) {

            return self::OUTCOME_VERY_NEGATIVE;

        }

        return self::OUTCOME_VERY_POSITIVE;

    }

    /**

     * get_analyser_class

     *

     * @return string

     */

    public function get_analyser_class() {

        return '\core\analytics\analyser\site_courses';

    }

    /**

     * We don't want to discard results.

     * @return float

     */

    protected function min_prediction_score() {

        return null;

    }

    /**

     * We don't want to discard results.

     * @return array

     */

    public function ignored_predicted_classes() {

        return array();

    }

    /**

     * is_valid_analysable

     *

     * @param \core_analytics\analysable $analysable

     * @param bool $fortraining

     * @return bool

     */

    public function is_valid_analysable(\core_analytics\analysable $analysable, $fortraining = true) {

        // This is testing, let's make things easy.

        return true;

    }

    /**

     * is_valid_sample

     *

     * @param int $sampleid

     * @param \core_analytics\analysable $analysable

     * @param bool $fortraining

     * @return bool

     */

    public function is_valid_sample($sampleid, \core_analytics\analysable $analysable, $fortraining = true) {

        // We skip not-visible courses during training as a way to emulate the training data / prediction data difference.

        // In normal circumstances is_valid_sample will return false when they receive a sample that can not be

        // processed.

        if (!$fortraining) {

            return true;

        }

        $sample = $this->retrieve('course', $sampleid);

        if ($sample->visible == 0) {

            return false;

        }

        return true;

    }

    /**

     * classes_description

     *

     * @return string[]

     */

    protected static function classes_description() {

        return array(

            get_string('first class'),

            get_string('second class'),

            get_string('third class')

        );

    }

    /**

     * calculate_sample

     *

     * @param int $sampleid

     * @param \core_analytics\analysable $analysable

     * @param int $starttime

     * @param int $endtime

     * @return float

     */

    protected function calculate_sample($sampleid, \core_analytics\analysable $analysable, $starttime = false, $endtime = false) {

        $sample = $this->retrieve('course', $sampleid);

        $firstchar = substr($sample->shortname, 0, 1);

        switch ($firstchar) {

            case 'a':

                return 0;

            case 'b':

                return 1;

            case 'c':

                return 2;

        }

    }

    /**

     * Can the provided time-splitting method be used on this target?.

     *

     * Time-splitting methods not matching the target requirements will not be selectable by models based on this target.

     *

     * @param \core_analytics\local\time_splitting\base $timesplitting

     * @return bool

     */

    public function can_use_timesplitting(\core_analytics\local\time_splitting\base $timesplitting): bool {

        return true;

    }

}