Google-sheets – Update Cell If another cell is not empty

I had to use script editor:

function onEdit(e) {
  var row = e.range.getRow();
  var dateCell = e.range.getSheet().getRange(row, 10);
  if (!dateCell.getValue()) {
    var distance = e.range.getSheet().getRange(row, 6).getValue();
    var A1 = e.range.getSheet().getRange(1, 1).getValue();
    dateCell.setValue(-(distance*A1/(15)));
  }
}

This is probably best handled by a custom function. The function I wrote takes the data range (including the header row) as an argument and outputs the new table, with Ids and its header. Usage example: =inOut(A1:C20). It also checks data for consistency: the times must begin with In and then alternate between In and Out.

function inOut(arr) {
  var data = {};
  var maxLen = 0;
  for (var i = 1; i < arr.length; i++) {
    var id = arr[i][0];
    if (!data[id]) {
      data[id] = [];
    }
    var expectedType = (data[id].length % 2 ? 'Out' : 'In');
    if (arr[i][1] != expectedType) {
      throw new Error('Inconsistent data on line ' + i + ': expected ' + expectedType + ' and got ' + arr[i][1]);
    }
    data[id].push(arr[i][2]);
    if (data[id].length > maxLen) {
      maxLen = data[id].length;
    }
  }

  // End of data collection; proceed to form output

  var keys = Object.keys(data).sort();
  var headerRow = ['EmpId'];
  for (i = 0; i < maxLen; i++) {
    headerRow.push(i % 2 ? 'Out' : 'In');
  }
  var output = [headerRow];
  for (i = 0; i < keys.length; i++) {
    id = keys[i];
    var row = [id].concat(data[id]);
    while (row.length < maxLen + 1) {
      row.push('');
    }
    output.push(row);
  }
  return output;
}