Current Path : C:/xampp/htdocs/moodle/analytics/classes/local/analysis/ |
Current File : C:/xampp/htdocs/moodle/analytics/classes/local/analysis/result_file.php |
<?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/>. /** * Keeps track of the analysis results by storing the results in files. * * @package core_analytics * @copyright 2019 David Monllao {@link http://www.davidmonllao.com} * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later */ namespace core_analytics\local\analysis; defined('MOODLE_INTERNAL') || die(); /** * Keeps track of the analysis results by storing the results in files. * * @package core_analytics * @copyright 2019 David Monllao {@link http://www.davidmonllao.com} * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later */ class result_file extends result { /** * Stores the analysis results by time-splitting method. * @var array */ private $filesbytimesplitting = []; /** * Stores the analysis results. * @param array $results * @return bool True if anything was successfully analysed */ public function add_analysable_results(array $results): bool { $any = false; // Process all provided time splitting methods. foreach ($results as $timesplittingid => $result) { if (!empty($result->result)) { $this->filesbytimesplitting[$timesplittingid][] = $result->result; $any = true; } } if (empty($any)) { return false; } return true; } /** * Retrieves cached results during evaluation. * * @param \core_analytics\local\time_splitting\base $timesplitting * @param \core_analytics\analysable $analysable * @return mixed A \stored_file in this case. */ public function retrieve_cached_result(\core_analytics\local\time_splitting\base $timesplitting, \core_analytics\analysable $analysable) { // For evaluation purposes we don't need to be that strict about how updated the data is, // if this analyser was analysed less that 1 week ago we skip generating a new one. This // helps scale the evaluation process as sites with tons of courses may need a lot of time to // complete an evaluation. if (!empty($this->options['evaluation']) && !empty($this->options['reuseprevanalysed'])) { $previousanalysis = \core_analytics\dataset_manager::get_evaluation_analysable_file($this->modelid, $analysable->get_id(), $timesplitting->get_id()); // 1 week is a partly random time interval, no need to worry about DST. $boundary = time() - WEEKSECS; if ($previousanalysis && $previousanalysis->get_timecreated() > $boundary) { // Recover the previous analysed file and avoid generating a new one. return $previousanalysis; } } return false; } /** * Formats the result. * * @param array $data * @param \core_analytics\local\target\base $target * @param \core_analytics\local\time_splitting\base $timesplitting * @param \core_analytics\analysable $analysable * @return mixed A \stored_file in this case */ public function format_result(array $data, \core_analytics\local\target\base $target, \core_analytics\local\time_splitting\base $timesplitting, \core_analytics\analysable $analysable) { if (!empty($this->includetarget)) { $filearea = \core_analytics\dataset_manager::LABELLED_FILEAREA; } else { $filearea = \core_analytics\dataset_manager::UNLABELLED_FILEAREA; } $dataset = new \core_analytics\dataset_manager($this->modelid, $analysable->get_id(), $timesplitting->get_id(), $filearea, $this->options['evaluation']); // Add extra metadata. $this->add_model_metadata($data, $timesplitting, $target); // Write all calculated data to a file. if (!$result = $dataset->store($data)) { return false; } return $result; } /** * Returns the results of the analysis. * @return array */ public function get(): array { if ($this->options['evaluation'] === false) { // Look for previous training and prediction files we generated and couldn't be used // by machine learning backends because they weren't big enough. $pendingfiles = \core_analytics\dataset_manager::get_pending_files($this->modelid, $this->includetarget, array_keys($this->filesbytimesplitting)); foreach ($pendingfiles as $timesplittingid => $files) { foreach ($files as $file) { $this->filesbytimesplitting[$timesplittingid][] = $file; } } } // We join the datasets by time splitting method. $timesplittingfiles = array(); foreach ($this->filesbytimesplitting as $timesplittingid => $files) { if ($this->options['evaluation'] === true) { // Delete the previous copy. Only when evaluating. \core_analytics\dataset_manager::delete_previous_evaluation_file($this->modelid, $timesplittingid); } // Merge all course files into one. if ($this->includetarget) { $filearea = \core_analytics\dataset_manager::LABELLED_FILEAREA; } else { $filearea = \core_analytics\dataset_manager::UNLABELLED_FILEAREA; } $timesplittingfiles[$timesplittingid] = \core_analytics\dataset_manager::merge_datasets($files, $this->modelid, $timesplittingid, $filearea, $this->options['evaluation']); } if (!empty($pendingfiles)) { // We must remove them now as they are already part of another dataset. foreach ($pendingfiles as $timesplittingid => $files) { foreach ($files as $file) { $file->delete(); } } } return $timesplittingfiles; } /** * Adds target metadata to the dataset. * * The final dataset document will look like this: * ---------------------------------------------------- * metadata1,metadata2,metadata3,..... * value1, value2, value3,..... * * header1,header2,header3,header4,..... * stud1value1,stud1value2,stud1value3,stud1value4,..... * stud2value1,stud2value2,stud2value3,stud2value4,..... * ..... * ---------------------------------------------------- * * @param array $data * @param \core_analytics\local\time_splitting\base $timesplitting * @param \core_analytics\local\target\base $target * @return null */ private function add_model_metadata(array &$data, \core_analytics\local\time_splitting\base $timesplitting, \core_analytics\local\target\base $target) { global $CFG; // If no target the first column is the sampleid, if target the last column is the target. // This will need to be updated when we support unsupervised learning models. $metadata = array( 'timesplitting' => $timesplitting->get_id(), 'nfeatures' => count(current($data)) - 1, 'moodleversion' => $CFG->version, 'targetcolumn' => $target->get_id() ); if ($target->is_linear()) { $metadata['targettype'] = 'linear'; $metadata['targetmin'] = $target::get_min_value(); $metadata['targetmax'] = $target::get_max_value(); } else { $metadata['targettype'] = 'discrete'; $metadata['targetclasses'] = json_encode($target::get_classes()); } // The first 2 samples will be used to store metadata about the dataset. $metadatacolumns = []; $metadatavalues = []; foreach ($metadata as $key => $value) { $metadatacolumns[] = $key; $metadatavalues[] = $value; } // This will also reset samples' dataset keys. array_unshift($data, $metadatacolumns, $metadatavalues); } }