/**
* See {@link GroupBy}.
*
* @param DataTable $table
*/
public function filter($table)
{
/** @var Row[] $groupByRows */
$groupByRows = array();
$nonGroupByRowIds = array();
foreach ($table->getRowsWithoutSummaryRow() as $rowId => $row) {
$groupByColumnValue = $row->getColumn($this->groupByColumn);
$groupByValue = $groupByColumnValue;
// reduce the group by column of this row
if ($this->reduceFunction) {
$parameters = array_merge(array($groupByColumnValue), $this->parameters);
$groupByValue = call_user_func_array($this->reduceFunction, $parameters);
}
if (!isset($groupByRows[$groupByValue])) {
// if we haven't encountered this group by value before, we mark this row as a
// row to keep, and change the group by column to the reduced value.
$groupByRows[$groupByValue] = $row;
$row->setColumn($this->groupByColumn, $groupByValue);
} else {
// if we have already encountered this group by value, we add this row to the
// row that will be kept, and mark this one for deletion
$groupByRows[$groupByValue]->sumRow($row, $copyMeta = true, $table->getMetadata(DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME));
$nonGroupByRowIds[] = $rowId;
}
}
if ($this->groupByColumn === 'label') {
$table->setLabelsHaveChanged();
}
// delete the unneeded rows.
$table->deleteRows($nonGroupByRowIds);
}