gistfile1.js

calculatesum=function(html){
    //! This function doesn't seem to do anything, since it's only ever called with an element's innerHTML.
    var tmp = document.createElement("DIV")
    tmp.innerHTML = html
    return tmp.textContent||tmp.innerText
}


getColumnCount=function() 
{
  return document.getElementById('tableEff').getElementsByTagName('tr')[0].getElementsByTagName('td').length;
}

getRowCount=function() 
{
    //! There is no property "rows" of Element:
    //! https://developer.mozilla.org/en-US/docs/Web/API/Element
    return document.getElementById('tableEff').rows.length;
}

resultEff=function(){

    //! Why -1? You use < in the loops (-1 is if you used <=)
    var lastCol = getColumnCount()-1;
    var lastRow = getRowCount()-1;

    var tbl = document.getElementById("tableEff");
    var NbCol=16; // Why not use column count?
    var totals = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];

    //! Why not getColumnCount?
    //! Also, you call `.length` on numbers, twice.
    for (var i = 0; i < NbCol.length; i++){ 
        for (var j = 0; j < lastRow.length; j++){
          var cell = lastRow[j].NbCol[i]
          //! Still not sure what calculatesum is doing here. Why not just innerText directly?
          var num = parseInt(calculatesum(cell.innerHTML), 10)

          /*alert(parseInt(calculatesum(cell.innerHTML), 10))
          console.log(parseInt(calculatesum(cell.innerHTML), 10))*/
          totals[i] += num
         // alert(totals[i])
          console.log(totals[i])
        }
       
    }
    console.log(totals[i])
    /*document.getElementById('TotalEff').innerHTML = "test: " + totals[1]
    console.log(totals[0])*/
    //alert(totals[0])
 
      var contenuTable=""
      for(var i = 0; i < 15; i++){
          contenuTable += "<td>" + totals[i] + "</td>"
      }
      var Table=  document.getElementById('table-totaux').innerHTML // an other table for the result
      //var trTable= Table.getElementsByTagName("tr").value
      //var Table.innerHTML(contenuTable)
  }