row append and calculation in jquery datatable

JavaScript
Plain text12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364$(document).ready(function() {      loadMyItems();  });    function loadMyItems() {        var siteUrl = _spPageContextInfo.siteAbsoluteUrl;    var oDataUrl = siteUrl + "link";      $.ajax({          url: oDataUrl,          type: "GET",          dataType: "json",          headers: {              "accept": "application/json;odata=verbose"          },          success: mySuccHandler,          error: myErrHandler      });  }      function mySuccHandler(data) {      try {            var dataTableExample = $('#table_id').DataTable();          if (dataTableExample != 'undefined') {              dataTableExample.destroy();          }            dataTableExample = $('#table_id').DataTable({            scrollY: 770,             "order": [[ 2, "asc" ]],             "pageLength": 50,            "aaData": data.d.results,              "aoColumns": [{                  "mData": "EditLink",                "render": function(EditLink) {                    return '<button onclick="EditItemWithCheckoutAlert(event, \''+EditLink+'\');">Edit</button>';               }            }, {                  "mData": "Title"            }, {                  "mData": "StartDate"            }, {                  "mData": "Planned_x0020_Date"             }, {                  "mData": "Days_x0020_of_x0020_delay"              }, {                  "mData": "Days_x0020_Left"              }, {                  "mData": "Reason_x0020_for_x0020_Late_x002",                "render": function( data, type, full, meta) {                    if(!data){var returnText = "";}                    else {var returnText = data.results;}                    return returnText;                    }              }]        });     } catch (e) {          alert(e.message);      }  }    function myErrHandler(data, errCode, errMessage) {      alert("Error: " + errMessage);  }
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