Row grouping with data from file

Karkuro

I have a working datatable that is retrieving data from a file :

http://i.imgur.com/ehrbZFF.png

I want to group row, something like this :

https://datatables.net/examples/advanced_init/row_grouping.html

My goal would to have my datatable to look like this, grouping row by the date (last column), but even looking at the code, I have trouble to make it work. I'd like some help to make that work if you could.

Here is the code of my datatable :

$(document).ready(function() {
         $('#datatable').DataTable( {
         "ajax": "<?php echo base_url()."assets/files/data/data.txt"; ?>" ,
         "columns": [
            { "data": "etat" },
            { "data": "dest" },
            { "data": "message" },
            { "data": "exp" },
            { "data": "date" }
            ],
            "order": [[ 0, "desc" ]],
            "responsive": true
            } );
         } );