function setClass(newClassName, obj)
{
  obj.className = newClassName;
}

function setCheckboxes(start, end, mode)
{
  for (i = start; i <= end; i++)
  {
    if (mode == 1)
    {
      document.getElementById(i).checked = true;
    }

    if (mode == 2)
    {
      document.getElementById(i).checked = false;
    }

    if (mode == 3)
    {
      value = document.getElementById(i).checked
      if (value) document.getElementById(i).checked = false;
      else document.getElementById(i).checked = true;
    }
  }
}

function setCheckbox(obj, mode)
{
  if (mode == 1)
  {
    document.getElementById(obj).checked = true;
  }

  if (mode == 2)
  {
    document.getElementById(obj).checked = false;
  }

  if (mode == 3)
  {
    value = document.getElementById(obj).checked
    if (value) document.getElementById(obj).checked = false;
    else document.getElementById(obj).checked = true;
  }
}

function isNumeric(obj)
{
  val = obj.value;

  if (isNaN(val))
  {
    obj.value = val.slice(0, val.length - 1);
  }
}