<?xml version="1.0" encoding="UTF-8" ?>
<dt-option group="callback">
	<name>footerCallback</name>
	<summary>Footer display callback function.</summary>
	<since>1.10</since>

	<type type="function">
		<signature>footerCallback( tfoot, data, start, end, display )</signature>
		<parameter type="node" name="tfoot">
			`-tag tfoot` element of the table's footer
		</parameter>
		<parameter type="array" name="data">
			Full data array of the table. Note that this is in data index order. Use the `display` parameter for the current display order.
		</parameter>
		<parameter type="integer" name="start">
			Index for the current display starting point in the display array
		</parameter>
		<parameter type="integer" name="end">
			Index for the current display ending point in the display array
		</parameter>
		<parameter type="array" name="display">
			Index array to translate the visual position to the full data array
		</parameter>
		<scope>HTML table element</scope>
	</type>

	<description>
		Identical to `dt-init headerCallback` but for the table footer this function allows you to modify the table footer on every 'draw' event.

		Note that if the table does not have a `-tag tfoot` element, it this callback will not be fired.
	</description>

	<example title="Alter the content of the footer on callback"><![CDATA[
$('#example').dataTable( {
  "footerCallback": function( tfoot, data, start, end, display ) {
    $(tfoot).find('th').eq(0).html( "Starting index is "+start );
  }
} );
]]></example>

	<example title="Use the API to sum a specific column and output"><![CDATA[
$('#example').dataTable( {
  "footerCallback": function( tfoot, data, start, end, display ) {
    var api = this.api();
    $( api.column( 5 ).footer() ).html(
    	api.column( 5 ).data().reduce( function ( a, b ) {
    		return a + b;
    	}, 0 )
    );
  }
} );
]]></example>

	<related type="option">headerCallback</related>
	<related type="option">drawCallback</related>
	<related type="api">columns().footer()</related>
	<related type="api">column().footer()</related>
</dt-option>