var arrFactors = new Array(5);
//var prevValue = 0;
var prevBox = null;
var decimalPlaces = 6;

arrFactors[1] = parseFloat('100');
arrFactors[2] = parseFloat('1000');
arrFactors[3] = parseFloat('1');
arrFactors[4] = parseFloat('0.001');
arrFactors[5] = parseFloat('39.37007874015748031496062992126');
arrFactors[6] = parseFloat('3.280839895');
arrFactors[7] = parseFloat('0.0049709695379');
arrFactors[8] = parseFloat('0.0002071237307458');
arrFactors[9] = parseFloat('6.2137119223733396961743418436332e-4');
arrFactors[10] = parseFloat('5.3995680345572354211663066954644e-4');
arrFactors[11] = parseFloat('0.54680664916885389326334208223972');
arrFactors[12] = parseFloat('1.09361329833770778652668416448');


function roundDP(n, decplaces) {
  var t = Number('1e' + decplaces);
  return Math.round(n * t) / t;
}

function convert(form, id) {
  var val, fromFactor, i;
  
  // start at 1 since 0 is catid element
  val = parseFloat(form["input" + id].value);
  //if (isNaN(val) || prevValue == val) return;
  if (isNaN(val)) return;

  if (val == '' || isNaN(val)) val = 0;
  fromFactor = arrFactors[id];
  
  for (i = 1; i <= 12; i++) 
    if (i != id) form["input" + i].value = roundDP(arrFactors[i] / fromFactor * val, decimalPlaces); 
}

function enterBox(form, id) {
  //prevValue = parseFloat(form["input" + id].value);
  // highlight the new box for visibility
  if (form["input" + id].style) {
    if (prevBox != null) {
      form["input" + prevBox].style.color = '';
      //document.getElementById('lbl' + prevBox).style.fontWeight = 'normal';
    }
    form["input" + id].style.color = '#0000ff';
    //document.getElementById('lbl' + id).style.fontWeight = 'bold';
  }
  prevBox = id;
}