public function validate($value) {
        if (!$this->wasvalidated) {
            $this->prepare_data($value, true);
        }
        return $this->validationerrors;
    }
public function validate($value) {
        if (!$this->wasvalidated) {
            $this->prepare_data($value, true);
        }
        return $this->validationerrors;
    }
public function validate ( $ value ) { if ( ! $ this -> wasvalidated ) { $ this -> prepare_data ( $ value , true ) ; } return $ this -> validationerrors ; }
Validates that rubric has at least one criterion, at least two levels within one criterion,
each level has a valid score, all levels have filled definitions and all criteria
have filled descriptions

@param array $value
@return string|false error text or false if no errors found
Validates that rubric has at least one criterion at least two levels within one criterion each level has a valid score all levels have filled definitions and all criteria have filled descriptions