<!-- Generic Unit Conversion Program

// Author    : Jonathan Weesner (jweesner@cyberstation.net)  21 Nov 95
// Angepasst und abgewandelt: Karl Ruess (k.ruess@rational-online.de)
// Typo3 Implementation Uwe Harnischmacher (uwe.harnischmacher@kontrast.de)


function convertform(form){
    var firstvalue = 0;
    for (var i = 0; i <= (form.count-1); i++) {

       // Find first non-blank entry
       if (form[i].value != null && form[i].value.length != 0) {
	  // Verify that value is a number
	  for (var j = 0; j < form[i].value.length; j++) {
	      var ch = form[i].value.substring(j, j + 1)
	      if ((ch < '0' || '9' < ch) && ch != '.') {
		 alert(' field has invalid data: ' + form[i].value);
		 clearform(form);
		 return false;
	      }
	  }
	  if (i == 1 && form[2].value != '') return false;
	  firstvalue = form[i].value / form[i].factor;
	  break;
       }
    }
    if (firstvalue == 0) {
       clearform(form);
       return false;
    }
    for (var i = 0; i <= (form.count-1); i++) {
	form[i].value = firstvalue * form[i].factor;
	form[i].value = formatvalue(form[i].value, form.rsize);
    }
    return true;
}
function formatvalue(input, rsize) {
   var invalid = '**************************';
   var nines = '999999999999999999999999';
   if (input.length <= rsize) return input;
   if (strpos(input, 'e') != -1 ||
       eval(input) > eval(nines.substring(0,rsize)+'.4'))
      return invalid.substring(0, rsize);
   var rounded = '' + (eval(input) +
		 (eval(input) - eval(input.substring(0, rsize))));
   return rounded.substring(0, rsize);
}
function strpos(str, ch) {
   for (var i = 0; i < str.length; i++)
      if (str.substring(i, i+1) == ch) return i;
   return -1;
}
function resetform(form) {
    clearform(form);
    form[1].value = 1;
    convertform(form);
    return true;
}
function clearform(form) {
    for (var i = 0; i <= (form.count-1); i++) form[i].value = '';
    return true;
}
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