Cells containing custom functions return “NaN'” when spreadsheet is not open. (Apps Script webapp accessing google spreadsheet)

Question

As a high school teacher, I record all of my grading in a Google spreadsheet. I have written custom functions within that spreadsheet that are accessed in the spreadsheet. T

Answer 1

With Eric's advice, I implemented the following function (which runs early on in my app):

function refreshSheet(spreadsheet, sheet) {
  var dataArrayRange = sheet.getRange(1,1,sheet.getLastRow(),sheet.getLastColumn());
  var dataArray = dataArrayRange.getValues(); // necessary to refresh custom functions
  var nanFound = true;
  while(nanFound) {
    for(var i = 0; i < dataArray.length; i++) {
      if(dataArray[i].indexOf('#N/A') >= 0) {
        nanFound = true;
        dataArray = dataArrayRange.getValues();
        break;
      } // end if
      else if(i == dataArray.length - 1) nanFound = false;
    } // end for
  } // end while
}

It basically keeps refreshing the sheet (using .getValues()) until all of the #N/A's disappear. It works fabulously but does add a small lag.