/**********************************************************************
 *
 *  足りない桁数を 0 で埋めた数値文字列を得る
 *
 *  Copyright (c) 2003, 2006 AOK <soft@aokura.com>
 *
 **********************************************************************/

function formatNum(keta, num) {
  var src = new String(num);
  var cnt = keta - src.length;
  if (cnt <= 0) return src;
  while (cnt-- > 0) src = "0" + src;
  return src;
}