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Differences Between: [Versions 39 and 400] [Versions 39 and 401] [Versions 39 and 402] [Versions 39 and 403]

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 3 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  /**
  18   * Defines the editing form for the calculated question data set items.
  19   *
  20   * @package    qtype
  21   * @subpackage calculated
  22   * @copyright  2007 Jamie Pratt me@jamiep.org
  23   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24   */
  25  
  26  
  27  defined('MOODLE_INTERNAL') || die();
  28  
  29  require_once($CFG->dirroot . '/question/type/edit_question_form.php');
  30  
  31  
  32  /**
  33   * Calculated question data set items editing form definition.
  34   *
  35   * @copyright  2007 Jamie Pratt me@jamiep.org
  36   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  37   */
  38  class question_dataset_dependent_items_form extends question_wizard_form {
  39      /**
  40       * Question object with options and answers already loaded by get_question_options
  41       * Be careful how you use this it is needed sometimes to set up the structure of the
  42       * form in definition_inner but data is always loaded into the form with set_defaults.
  43       *
  44       * @var object
  45       */
  46      public $question;
  47      /**
  48       * Reference to question type object
  49       *
  50       * @var question_dataset_dependent_questiontype
  51       */
  52      public $qtypeobj;
  53  
  54      /** @var stdClass the question category. */
  55      protected $category;
  56  
  57      /** @var context the context of the question category. */
  58      protected $categorycontext;
  59  
  60      public $datasetdefs;
  61  
  62      public $maxnumber = -1;
  63  
  64      public $regenerate;
  65  
  66      public $noofitems;
  67  
  68      public $outsidelimit = false;
  69  
  70      public $commentanswers = array();
  71  
  72      /**
  73       * Add question-type specific form fields.
  74       *
  75       * @param MoodleQuickForm $mform the form being built.
  76       */
  77      public function __construct($submiturl, $question, $regenerate) {
  78          global $SESSION, $CFG, $DB;
  79          $this->regenerate = $regenerate;
  80          $this->question = $question;
  81          $this->qtypeobj = question_bank::get_qtype($this->question->qtype);
  82          // Validate the question category.
  83          if (!$category = $DB->get_record('question_categories',
  84                  array('id' => $question->category))) {
  85              print_error('categorydoesnotexist', 'question', $returnurl);
  86          }
  87          $this->category = $category;
  88          $this->categorycontext = context::instance_by_id($category->contextid);
  89          // Get the dataset defintions for this question.
  90          if (empty($question->id)) {
  91              $this->datasetdefs = $this->qtypeobj->get_dataset_definitions(
  92                      $question->id, $SESSION->calculated->definitionform->dataset);
  93          } else {
  94              if (empty($question->options)) {
  95                  $this->get_question_options($question);
  96              }
  97              $this->datasetdefs = $this->qtypeobj->get_dataset_definitions(
  98                      $question->id, array());
  99          }
 100  
 101          foreach ($this->datasetdefs as $datasetdef) {
 102              // Get maxnumber.
 103              if ($this->maxnumber == -1 || $datasetdef->itemcount < $this->maxnumber) {
 104                  $this->maxnumber = $datasetdef->itemcount;
 105              }
 106          }
 107          foreach ($this->datasetdefs as $defid => $datasetdef) {
 108              if (isset($datasetdef->id)) {
 109                  $this->datasetdefs[$defid]->items =
 110                          $this->qtypeobj->get_database_dataset_items($datasetdef->id);
 111              }
 112          }
 113          parent::__construct($submiturl);
 114      }
 115  
 116      protected function definition() {
 117          global $PAGE;
 118  
 119          $labelsharedwildcard = get_string("sharedwildcard", "qtype_calculated");
 120          $mform = $this->_form;
 121          $mform->setDisableShortforms();
 122  
 123          $strquestionlabel = $this->qtypeobj->comment_header($this->question);
 124          if ($this->maxnumber != -1 ) {
 125              $this->noofitems = $this->maxnumber;
 126          } else {
 127              $this->noofitems = 0;
 128          }
 129          $label = get_string("sharedwildcards", "qtype_calculated");
 130  
 131          $html2 = $this->qtypeobj->print_dataset_definitions_category_shared(
 132                  $this->question, $this->datasetdefs);
 133          $mform->addElement('static', 'listcategory', $label, $html2);
 134          // ...----------------------------------------------------------------------.
 135          $mform->addElement('submit', 'updatedatasets',
 136                  get_string('updatedatasetparam', 'qtype_calculated'));
 137          $mform->registerNoSubmitButton('updatedatasets');
 138          $mform->addElement('header', 'additemhdr',
 139                  get_string('itemtoadd', 'qtype_calculated'));
 140          $idx = 1;
 141          $data = array();
 142          $j = (($this->noofitems) * count($this->datasetdefs))+1;
 143          foreach ($this->datasetdefs as $defkey => $datasetdef) {
 144              if ($datasetdef->category |= 0 ) {
 145                  $name = get_string('sharedwildcard', 'qtype_calculated', $datasetdef->name);
 146              } else {
 147                  $name = get_string('wildcard', 'qtype_calculated', $datasetdef->name);
 148              }
 149              $mform->addElement('float', "number[{$j}]", $name);
 150              $this->qtypeobj->custom_generator_tools_part($mform, $idx, $j);
 151              $idx++;
 152              $mform->addElement('hidden', "definition[{$j}]");
 153              $mform->setType("definition[{$j}]", PARAM_RAW);
 154              $mform->addElement('hidden', "itemid[{$j}]");
 155              $mform->setType("itemid[{$j}]", PARAM_RAW);
 156              $mform->addElement('static', "divider[{$j}]", '', '<hr />');
 157              $mform->setType("divider[{$j}]", PARAM_RAW);
 158              $j++;
 159          }
 160  
 161          $mform->addElement('header', 'updateanswershdr',
 162                  get_string('answerstoleranceparam', 'qtype_calculated'));
 163          $mform->addElement('submit', 'updateanswers',
 164                  get_string('updatetolerancesparam', 'qtype_calculated'));
 165          $mform->setAdvanced('updateanswers', true);
 166          $mform->registerNoSubmitButton('updateanswers');
 167  
 168          $answers = fullclone($this->question->options->answers);
 169          $key1 =1;
 170          foreach ($answers as $key => $answer) {
 171              $ans = shorten_text($answer->answer, 17, true);
 172              if ($ans === '*') {
 173                  $mform->addElement('static',
 174                          'answercomment[' . ($this->noofitems+$key1) . ']', $ans);
 175                  $mform->addElement('hidden', 'tolerance['.$key.']', '');
 176                  $mform->setType('tolerance['.$key.']', PARAM_FLOAT); // No need to worry about localisation, as the value of this field will not be shown to users anymore.
 177                  $mform->setAdvanced('tolerance['.$key.']', true);
 178                  $mform->addElement('hidden', 'tolerancetype['.$key.']', '');
 179                  $mform->setType('tolerancetype['.$key.']', PARAM_RAW);
 180                  $mform->setAdvanced('tolerancetype['.$key.']', true);
 181                  $mform->addElement('hidden', 'correctanswerlength['.$key.']', '');
 182                  $mform->setType('correctanswerlength['.$key.']', PARAM_RAW);
 183                  $mform->setAdvanced('correctanswerlength['.$key.']', true);
 184                  $mform->addElement('hidden', 'correctanswerformat['.$key.']', '');
 185                  $mform->setType('correctanswerformat['.$key.']', PARAM_RAW);
 186                  $mform->setAdvanced('correctanswerformat['.$key.']', true);
 187              } else if ( $ans !== '' ) {
 188                  $mform->addElement('static', 'answercomment[' . ($this->noofitems+$key1) . ']',
 189                          $ans);
 190                  $mform->addElement('float', 'tolerance['.$key.']',
 191                          get_string('tolerance', 'qtype_calculated'));
 192                  $mform->setAdvanced('tolerance['.$key.']', true);
 193                  $mform->addElement('select', 'tolerancetype['.$key.']',
 194                          get_string('tolerancetype', 'qtype_numerical'),
 195                          $this->qtypeobj->tolerance_types());
 196                  $mform->setAdvanced('tolerancetype['.$key.']', true);
 197  
 198                  $mform->addElement('select', 'correctanswerlength['.$key.']',
 199                          get_string('correctanswershows', 'qtype_calculated'), range(0, 9));
 200                  $mform->setAdvanced('correctanswerlength['.$key.']', true);
 201  
 202                  $answerlengthformats = array(
 203                      '1' => get_string('decimalformat', 'qtype_numerical'),
 204                      '2' => get_string('significantfiguresformat', 'qtype_calculated')
 205                  );
 206                  $mform->addElement('select', 'correctanswerformat['.$key.']',
 207                          get_string('correctanswershowsformat', 'qtype_calculated'),
 208                          $answerlengthformats);
 209                  $mform->setAdvanced('correctanswerformat['.$key.']', true);
 210                  $mform->addElement('static', 'dividertolerance', '', '<hr />');
 211                  $mform->setAdvanced('dividertolerance', true);
 212              }
 213              $key1++;
 214          }
 215  
 216          $addremoveoptions = array();
 217          $addremoveoptions['1']='1';
 218          for ($i=10; $i<=100; $i+=10) {
 219               $addremoveoptions["{$i}"] = "{$i}";
 220          }
 221          $showoptions = Array();
 222          $showoptions['1']='1';
 223          $showoptions['2']='2';
 224          $showoptions['5']='5';
 225          for ($i=10; $i<=100; $i+=10) {
 226               $showoptions["{$i}"] = "{$i}";
 227          }
 228          $mform->addElement('header', 'addhdr', get_string('add', 'moodle'));
 229          $mform->closeHeaderBefore('addhdr');
 230  
 231          if ($this->qtypeobj->supports_dataset_item_generation()) {
 232              $radiogrp = array();
 233              $radiogrp[] =& $mform->createElement('radio', 'nextpageparam[forceregeneration]',
 234                      null, get_string('reuseifpossible', 'qtype_calculated'), 0);
 235              $radiogrp[] =& $mform->createElement('radio', 'nextpageparam[forceregeneration]',
 236                      null, get_string('forceregenerationshared', 'qtype_calculated'), 1);
 237              $radiogrp[] =& $mform->createElement('radio', 'nextpageparam[forceregeneration]',
 238                      null, get_string('forceregenerationall', 'qtype_calculated'), 2);
 239              $mform->addGroup($radiogrp, 'forceregenerationgrp',
 240                      get_string('nextitemtoadd', 'qtype_calculated'), "<br/>", false);
 241          }
 242  
 243          $mform->addElement('submit', 'getnextbutton', get_string('getnextnow', 'qtype_calculated'));
 244          $mform->addElement('static', "dividera", '', '<hr />');
 245          $addgrp = array();
 246          $addgrp[] =& $mform->createElement('submit', 'addbutton', get_string('add', 'moodle'));
 247          $addgrp[] =& $mform->createElement('select', "selectadd",
 248                  get_string('additem', 'qtype_calculated'), $addremoveoptions);
 249          $addgrp[] = & $mform->createElement('static', "stat", "Items",
 250                  get_string('newsetwildcardvalues', 'qtype_calculatedsimple'));
 251          $mform->addGroup($addgrp, 'addgrp', get_string('additem', 'qtype_calculated'), ' ', false);
 252          $mform->addElement('static', "divideradd", '', '');
 253          if ($this->noofitems > 0) {
 254              $mform->addElement('header', 'deleteitemhdr', get_string('delete', 'moodle'));
 255              $deletegrp = array();
 256              $deletegrp[] = $mform->createElement('submit', 'deletebutton',
 257                      get_string('delete', 'moodle'));
 258              $deletegrp[] = $mform->createElement('select', 'selectdelete',
 259                      get_string('deleteitem', 'qtype_calculated')."1", $addremoveoptions);
 260              $deletegrp[] = $mform->createElement('static', "stat", "Items",
 261                      get_string('setwildcardvalues', 'qtype_calculatedsimple'));
 262              $mform->addGroup($deletegrp, 'deletegrp', '', '   ', false);
 263          } else {
 264              $mform->addElement('static', 'warning', '', '<span class="error">' .
 265                      get_string('youmustaddatleastoneitem', 'qtype_calculated').'</span>');
 266          }
 267  
 268          $addgrp1 = array();
 269          $addgrp1[] = $mform->createElement('submit', 'showbutton',
 270                  get_string('showitems', 'qtype_calculated'));
 271          $addgrp1[] = $mform->createElement('select', "selectshow", '' , $showoptions);
 272          $addgrp1[] = $mform->createElement('static', "stat", '',
 273                  get_string('setwildcardvalues', 'qtype_calculated'));
 274          $mform->addGroup($addgrp1, 'addgrp1', '', '   ', false);
 275          $mform->registerNoSubmitButton('showbutton');
 276          $mform->closeHeaderBefore('addgrp1');
 277          // ...----------------------------------------------------------------------.
 278          $j = $this->noofitems * count($this->datasetdefs);
 279          $k = optional_param('selectshow', 1, PARAM_INT);
 280          for ($i = $this->noofitems; $i >= 1; $i--) {
 281              if ($k > 0) {
 282                  $mform->addElement('header', 'setnoheader' . $i, "<b>" .
 283                          get_string('setno', 'qtype_calculated', $i)."</b>&nbsp;&nbsp;");
 284              }
 285              foreach ($this->datasetdefs as $defkey => $datasetdef) {
 286                  if ($k > 0) {
 287                      if ($datasetdef->category == 0 ) {
 288                          $mform->addElement('float', "number[{$j}]",
 289                                  get_string('wildcard', 'qtype_calculated', $datasetdef->name));
 290                      } else {
 291                          $mform->addElement('float', "number[{$j}]", get_string(
 292                                  'sharedwildcard', 'qtype_calculated', $datasetdef->name));
 293                      }
 294  
 295                  } else {
 296                      $mform->addElement('hidden', "number[{$j}]" , '');
 297                      $mform->setType("number[{$j}]", PARAM_LOCALISEDFLOAT); // Localisation handling has to be done manually.
 298                  }
 299                  $mform->addElement('hidden', "itemid[{$j}]");
 300                  $mform->setType("itemid[{$j}]", PARAM_INT);
 301  
 302                  $mform->addElement('hidden', "definition[{$j}]");
 303                  $mform->setType("definition[{$j}]", PARAM_NOTAGS);
 304                  $data[$datasetdef->name] =$datasetdef->items[$i]->value;
 305  
 306                  $j--;
 307              }
 308              if ('' != $strquestionlabel && ($k > 0 )) {
 309                  // ... $this->outsidelimit || !empty($this->numbererrors ).
 310                  $repeated[] = $mform->addElement('static', "answercomment[{$i}]", $strquestionlabel);
 311                  // Decode equations in question text.
 312                  $qtext = $this->qtypeobj->substitute_variables(
 313                          $this->question->questiontext, $data);
 314                  $textequations = $this->qtypeobj->find_formulas($qtext);
 315                  if ($textequations != '' && count($textequations) > 0 ) {
 316                      $mform->addElement('static', "divider1[{$j}]", '',
 317                              'Formulas {=..} in question text');
 318                      foreach ($textequations as $key => $equation) {
 319                          if ($formulaerrors = qtype_calculated_find_formula_errors($equation)) {
 320                              $str = $formulaerrors;
 321                          } else {
 322                              eval('$str = '.$equation.';');
 323                          }
 324                          $equation = shorten_text($equation, 17, true);
 325                          $mform->addElement('static', "textequation", "{={$equation}}", "=".$str);
 326                      }
 327                  }
 328  
 329              }
 330              $k--;
 331  
 332          }
 333          $mform->addElement('static', 'outsidelimit', '', '');
 334  
 335          // Submit buttons.
 336          if ($this->noofitems > 0) {
 337              $buttonarray = array();
 338              $buttonarray[] = $mform->createElement(
 339                      'submit', 'savechanges', get_string('savechanges'));
 340  
 341              $previewlink = $PAGE->get_renderer('core_question')->question_preview_link(
 342                          $this->question->id, $this->categorycontext, true);
 343              $buttonarray[] = $mform->createElement('static', 'previewlink', '', $previewlink);
 344  
 345              $mform->addGroup($buttonarray, 'buttonar', '', array(' '), false);
 346              $mform->closeHeaderBefore('buttonar');
 347          }
 348  
 349          $this->add_hidden_fields();
 350  
 351          $mform->addElement('hidden', 'category');
 352          $mform->setType('category', PARAM_SEQUENCE);
 353  
 354          $mform->addElement('hidden', 'wizard', 'datasetitems');
 355          $mform->setType('wizard', PARAM_ALPHA);
 356      }
 357  
 358      public function set_data($question) {
 359          $formdata = array();
 360          $fromform = new stdClass();
 361          if (isset($question->options)) {
 362              $answers = $question->options->answers;
 363              if (count($answers)) {
 364                  if (optional_param('updateanswers', false, PARAM_BOOL) ||
 365                          optional_param('updatedatasets', false, PARAM_BOOL)) {
 366                      foreach ($answers as $key => $answer) {
 367                          $fromform->tolerance[$key]= $this->_form->getElementValue(
 368                                  'tolerance['.$key.']');
 369                          $answer->tolerance = $fromform->tolerance[$key];
 370                          $fromform->tolerancetype[$key]= $this->_form->getElementValue(
 371                                  'tolerancetype['.$key.']');
 372                          if (is_array($fromform->tolerancetype[$key])) {
 373                              $fromform->tolerancetype[$key]= $fromform->tolerancetype[$key][0];
 374                          }
 375                          $answer->tolerancetype = $fromform->tolerancetype[$key];
 376                          $fromform->correctanswerlength[$key]= $this->_form->getElementValue(
 377                                  'correctanswerlength['.$key.']');
 378                          if (is_array($fromform->correctanswerlength[$key])) {
 379                              $fromform->correctanswerlength[$key] =
 380                                      $fromform->correctanswerlength[$key][0];
 381                          }
 382                          $answer->correctanswerlength = $fromform->correctanswerlength[$key];
 383                          $fromform->correctanswerformat[$key] = $this->_form->getElementValue(
 384                                  'correctanswerformat['.$key.']');
 385                          if (is_array($fromform->correctanswerformat[$key])) {
 386                              $fromform->correctanswerformat[$key] =
 387                                      $fromform->correctanswerformat[$key][0];
 388                          }
 389                          $answer->correctanswerformat = $fromform->correctanswerformat[$key];
 390                      }
 391                      $this->qtypeobj->save_question_calculated($question, $fromform);
 392  
 393                  } else {
 394                      foreach ($answers as $key => $answer) {
 395                          $formdata['tolerance['.$key.']'] = $answer->tolerance;
 396                          $formdata['tolerancetype['.$key.']'] = $answer->tolerancetype;
 397                          $formdata['correctanswerlength['.$key.']'] = $answer->correctanswerlength;
 398                          $formdata['correctanswerformat['.$key.']'] = $answer->correctanswerformat;
 399                      }
 400                  }
 401              }
 402          }
 403          // Fill out all data sets and also the fields for the next item to add.
 404          $j = $this->noofitems * count($this->datasetdefs);
 405          for ($itemnumber = $this->noofitems; $itemnumber >= 1; $itemnumber--) {
 406              $data = array();
 407              foreach ($this->datasetdefs as $defid => $datasetdef) {
 408                  if (isset($datasetdef->items[$itemnumber])) {
 409                      $value = $datasetdef->items[$itemnumber]->value;
 410                      if ($this->_form->getElementType("number[{$j}]") == 'hidden') {
 411                          // Some of the number elements are from the float type and some are from the hidden type.
 412                          // We need to manually handle localised floats for hidden elements.
 413                          $value = format_float($value, -1);
 414                      }
 415                      $formdata["number[{$j}]"] = $value;
 416                      $formdata["definition[{$j}]"] = $defid;
 417                      $formdata["itemid[{$j}]"] = $datasetdef->items[$itemnumber]->id;
 418                      $data[$datasetdef->name] = $datasetdef->items[$itemnumber]->value;
 419                  }
 420                  $j--;
 421              }
 422              $comment = $this->qtypeobj->comment_on_datasetitems($this->qtypeobj, $question->id,
 423                      $question->questiontext, $answers, $data, $itemnumber);
 424              if ($comment->outsidelimit) {
 425                  $this->outsidelimit=$comment->outsidelimit;
 426              }
 427              $totalcomment='';
 428              foreach ($question->options->answers as $key => $answer) {
 429                  $totalcomment .= $comment->stranswers[$key].'<br/>';
 430              }
 431              $formdata['answercomment['.$itemnumber.']'] = $totalcomment;
 432          }
 433  
 434          $formdata['nextpageparam[forceregeneration]'] = $this->regenerate;
 435          $formdata['selectdelete'] = '1';
 436          $formdata['selectadd'] = '1';
 437          $j = $this->noofitems * count($this->datasetdefs)+1;
 438          $data = array(); // Data for comment_on_datasetitems later.
 439          // Dataset generation defaults.
 440          if ($this->qtypeobj->supports_dataset_item_generation()) {
 441              $itemnumber = $this->noofitems+1;
 442              foreach ($this->datasetdefs as $defid => $datasetdef) {
 443                  if (!optional_param('updatedatasets', false, PARAM_BOOL) &&
 444                          !optional_param('updateanswers', false, PARAM_BOOL)) {
 445                      $value = $this->qtypeobj->generate_dataset_item($datasetdef->options);
 446                  } else {
 447                      $value = $this->_form->getElementValue("number[{$j}]");
 448                  }
 449                  if ($this->_form->getElementType("number[{$j}]") == 'hidden') {
 450                      // Some of the number elements are from the float type and some are from the hidden type.
 451                      // We need to manually handle localised floats for hidden elements.
 452                      $value = format_float($value, -1);
 453                  }
 454                  $formdata["number[{$j}]"] = $value;
 455                  $formdata["definition[{$j}]"] = $defid;
 456                  $formdata["itemid[{$j}]"] = isset($datasetdef->items[$itemnumber]) ?
 457                          $datasetdef->items[$itemnumber]->id : 0;
 458                  $data[$datasetdef->name] = $formdata["number[{$j}]"];
 459                  $j++;
 460              }
 461          }
 462  
 463          // Existing records override generated data depending on radio element.
 464          $j = $this->noofitems * count($this->datasetdefs) + 1;
 465          if (!$this->regenerate && !optional_param('updatedatasets', false, PARAM_BOOL) &&
 466                  !optional_param('updateanswers', false, PARAM_BOOL)) {
 467              $itemnumber = $this->noofitems + 1;
 468              foreach ($this->datasetdefs as $defid => $datasetdef) {
 469                  if (isset($datasetdef->items[$itemnumber])) {
 470                      $formdata["number[{$j}]"] = $datasetdef->items[$itemnumber]->value;
 471                      $formdata["definition[{$j}]"] = $defid;
 472                      $formdata["itemid[{$j}]"] = $datasetdef->items[$itemnumber]->id;
 473                      $data[$datasetdef->name] = $datasetdef->items[$itemnumber]->value;
 474                  }
 475                  $j++;
 476              }
 477          }
 478  
 479          $comment = $this->qtypeobj->comment_on_datasetitems($this->qtypeobj, $question->id,
 480                  $question->questiontext, $answers, $data, ($this->noofitems + 1));
 481          if (isset($comment->outsidelimit) && $comment->outsidelimit) {
 482              $this->outsidelimit=$comment->outsidelimit;
 483          }
 484          $key1 = 1;
 485          foreach ($question->options->answers as $key => $answer) {
 486              $formdata['answercomment['.($this->noofitems+$key1).']'] = $comment->stranswers[$key];
 487              $key1++;
 488          }
 489  
 490          if ($this->outsidelimit) {
 491              $formdata['outsidelimit']= '<span class="error">' .
 492                      get_string('oneanswertrueansweroutsidelimits', 'qtype_calculated') . '</span>';
 493          }
 494          $formdata = $this->qtypeobj->custom_generator_set_data($this->datasetdefs, $formdata);
 495  
 496          parent::set_data((object)($formdata + (array)$question));
 497      }
 498  
 499      public function validation($data, $files) {
 500          $errors = array();
 501          if (isset($data['savechanges']) && ($this->noofitems==0) ) {
 502              $errors['warning'] = get_string('warning', 'mnet');
 503          }
 504          if ($this->outsidelimit) {
 505              $errors['outsidelimits'] =
 506                      get_string('oneanswertrueansweroutsidelimits', 'qtype_calculated');
 507          }
 508          $numbers = $data['number'];
 509          foreach ($numbers as $key => $number) {
 510              if (! is_numeric($number)) {
 511                  if (stristr($number, ',')) {
 512                      $errors['number['.$key.']'] = get_string('nocommaallowed', 'qtype_calculated');
 513                  } else {
 514                      $errors['number['.$key.']'] = get_string('notvalidnumber', 'qtype_calculated');
 515                  }
 516              } else if (stristr($number, 'x')) {
 517                  $a = new stdClass();
 518                  $a->name = '';
 519                  $a->value = $number;
 520                  $errors['number['.$key.']'] = get_string('hexanotallowed', 'qtype_calculated', $a);
 521              } else if (is_nan($number)) {
 522                  $errors['number['.$key.']'] = get_string('notvalidnumber', 'qtype_calculated');
 523              }
 524          }
 525          return $errors;
 526      }
 527  }