question/classes/statistics/responses/analysis_for_class.php

   1 <?php
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   3 //
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  16
  17 /**
  18  * @package    core_question
  19  * @copyright  2013 The Open University
  20  * @author     James Pratt me@jamiep.org
  21  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  22  */
  23
  24 namespace core_question\statistics\responses;
  25
  26
  27
  28 /**
  29  * Counts a class of responses for this sub part of the question.
  30  *
  31  * No response is one possible class of response to a question.
  32  *
  33  * - There is a separate data structure for each question or sub question's analysis
  34  * {@link \core_question\statistics\responses\analysis_for_question}
  35  * or {@link \core_question\statistics\responses\analysis_for_question_all_tries}.
  36  * - There are separate analysis for each variant in this top level instance.
  37  * - Then there are class instances representing the analysis of each of the sub parts of each variant of the question.
  38  * {@link \core_question\statistics\responses\analysis_for_subpart}.
  39  * - Then within the sub part analysis there are response class analysis
  40  * {@link \core_question\statistics\responses\analysis_for_class}.
  41  * - Then within each class analysis there are analysis for each actual response
  42  * {@link \core_question\statistics\responses\analysis_for_actual_response}.
  43  *
  44  * @package    core_question
  45  * @copyright  2014 The Open University
  46  * @author     James Pratt me@jamiep.org
  47  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  48  */
  49 class analysis_for_class {
  50
  51     /**
  52      * @var string must be unique for each response class within this sub part.
  53      */
  54     protected $responseclassid;
  55
  56     /**
  57      * @var string represent this class in the response analysis table.
  58      */
  59     protected $modelresponse;
  60
  61     /** @var string the (partial) credit awarded for this responses. */
  62     protected $fraction;
  63
  64     /** @var analysis_for_actual_response[] key is the actual response represented as a string as it will be displayed in report.
  65      */
  66     protected $actualresponses = array();
  67
  68     /**
  69      * Constructor, just an easy way to set the fields.
  70      *
  71      * @param \question_possible_response $possibleresponse
  72      * @param string                      $responseclassid
  73      */
  74     public function __construct($possibleresponse, $responseclassid) {
  75         $this->modelresponse = $possibleresponse->responseclass;
  76         $this->fraction = $possibleresponse->fraction;
  77         $this->responseclassid = $responseclassid;
  78     }
  79
  80     /**
  81      * Keep a count of a response to this question sub part that falls within this class.
  82      *
  83      * @param string     $actualresponse
  84      * @param float|null $fraction
  85      * @param int        $try
  86      * @return \core_question\statistics\responses\analysis_for_actual_response
  87      */
  88     public function count_response($actualresponse, $fraction, $try) {
  89         if (!isset($this->actualresponses[$actualresponse])) {
  90             if ($fraction === null) {
  91                 $fraction = $this->fraction;
  92             }
  93             $this->add_response($actualresponse, $fraction);
  94         }
  95         $this->get_response($actualresponse)->increment_count($try);
  96     }
  97
  98     /**
  99      * Cache analysis for class.
 100      *
 101      * @param \qubaid_condition $qubaids    which question usages have been analysed.
 102      * @param string            $whichtries which tries have been analysed?
 103      * @param int               $questionid which question.
 104      * @param int               $variantno  which variant.
 105      * @param string            $subpartid  which sub part.
 106      * @param int|null          $calculationtime time when the analysis was done. (Defaults to time()).
 107      */
 108     public function cache($qubaids, $whichtries, $questionid, $variantno, $subpartid, $calculationtime = null) {
 109         foreach ($this->get_responses() as $response) {
 110             $analysisforactualresponse = $this->get_response($response);
 111             $analysisforactualresponse->cache($qubaids, $whichtries, $questionid, $variantno, $subpartid,
 112                     $this->responseclassid, $calculationtime);
 113         }
 114     }
 115
 116     /**
 117      * Add an actual response to the data structure.
 118      *
 119      * @param string $response A string representing the actual response.
 120      * @param float  $fraction The fraction of grade awarded for this response.
 121      */
 122     public function add_response($response, $fraction) {
 123         $this->actualresponses[$response] = new analysis_for_actual_response($response, $fraction);
 124     }
 125
 126     /**
 127      * Used when loading cached counts.
 128      *
 129      * @param string $response
 130      * @param int $try the try number, will be zero if not keeping track of try.
 131      * @param int $count the count
 132      */
 133     public function set_response_count($response, $try, $count) {
 134         $this->actualresponses[$response]->set_count($try, $count);
 135     }
 136
 137     /**
 138      * Are there actual responses to sub parts that where classified into this class?
 139      *
 140      * @return bool whether this analysis has a response class with more than one
 141      *      different actual response, or if the actual response is different from
 142      *      the model response.
 143      */
 144     public function has_actual_responses() {
 145         $actualresponses = $this->get_responses();
 146         if (count($actualresponses) > 1) {
 147             return true;
 148         } else if (count($actualresponses) === 1) {
 149             $singleactualresponse = reset($actualresponses);
 150             return (string)$singleactualresponse !== (string)$this->modelresponse;
 151         }
 152         return false;
 153     }
 154
 155     /**
 156      * Return the data to display in the response analysis table.
 157      *
 158      * @param bool $responseclasscolumn
 159      * @param string $partid
 160      * @return object[]
 161      */
 162     public function data_for_question_response_table($responseclasscolumn, $partid) {
 163         $return = array();
 164         if (count($this->get_responses()) == 0) {
 165             $rowdata = new \stdClass();
 166             $rowdata->part = $partid;
 167             $rowdata->responseclass = $this->modelresponse;
 168             if (!$responseclasscolumn) {
 169                 $rowdata->response = $this->modelresponse;
 170             } else {
 171                 $rowdata->response = '';
 172             }
 173             $rowdata->fraction = $this->fraction;
 174             $rowdata->totalcount = 0;
 175             $rowdata->trycount = array();
 176             $return[] = $rowdata;
 177         } else {
 178             foreach ($this->get_responses() as $actualresponse) {
 179                 $response = $this->get_response($actualresponse);
 180                 $return[] = $response->data_for_question_response_table($partid, $this->modelresponse);
 181             }
 182         }
 183         return $return;
 184     }
 185
 186     /**
 187      * What is the highest try number that an actual response of this response class has been seen?
 188      *
 189      * @return int try number
 190      */
 191     public function get_maximum_tries() {
 192         $max = 1;
 193         foreach ($this->get_responses() as $actualresponse) {
 194             $max = max($max, $this->get_response($actualresponse)->get_maximum_tries());
 195         }
 196         return $max;
 197     }
 198
 199     /**
 200      * Return array of the actual responses to this sub part that were classified into this class.
 201      *
 202      * @return string[] the actual responses we are counting tries at.
 203      */
 204     protected function get_responses() {
 205         return array_keys($this->actualresponses);
 206     }
 207
 208     /**
 209      * Get the data structure used to count the responses that match an actual response within this class of responses.
 210      *
 211      * @param string $response
 212      * @return analysis_for_actual_response the instance for keeping count of tries for $response.
 213      */
 214     protected function get_response($response) {
 215         return $this->actualresponses[$response];
 216     }
 217 }