/*
Copyright © 2005 fishfriend.com, Leon Huang. All Rights Reserved.
Users are prohibited from modifying, copying, distributing, transmitting, displaying, publishing, 
selling, licensing, creating derivative works or using any part of this JavaScript for commercial 
or public purposes.
*/

<!--
function MM_findObj(n, d) { //v4.01
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function MM_validateForm() { //v4.0
  var i,p,q,nm,test,num,min,max,errors='',args=MM_validateForm.arguments;
  for (i=0; i<(args.length-2); i+=3) { test=args[i+2]; val=MM_findObj(args[i]);
    if (val) { nm=val.name; if ((val=val.value)!="") {
      if (test.indexOf('isEmail')!=-1) { p=val.indexOf('@');
        if (p<1 || p==(val.length-1)) errors+='- '+nm+' must contain an e-mail address.\n';
      } else if (test!='R') { num = parseFloat(val);
        if (isNaN(val)) errors+='- '+nm+' must contain a number.\n';
        if (test.indexOf('inRange') != -1) { p=test.indexOf(':');
          min=test.substring(8,p); max=test.substring(p+1);
          if (num<min || max<num) errors+='- '+nm+' must contain a number between '+min+' and '+max+'.\n';
    } } } else if (test.charAt(0) == 'R') errors += '- '+nm+' is required.\n'; }
  } if (errors) alert('The following error(s) occurred:\n'+errors);
  document.MM_returnValue = (errors == '');
}

function MM_callJS(jsStr) { //v2.0
  return eval(jsStr)
}

function Calc_CO2() {
	var intPH, intKH, strUnit;
	var intPower, intCO2;

	//Get measurements
	intPH = document.forms[1].txtPH.value;
	intKH = document.forms[1].txtKH.value;

	//Get measurements unit
	for (var i=0; i<document.forms[1].rgrpUnit.length; i++)  {
		if (document.forms[1].rgrpUnit[i].checked)  {
			strUnit = document.forms[1].rgrpUnit[i].value
		}
	}

	//Convert to cm
	switch (strUnit) {
		case "degrees":
			break;
		case "ppm":
		  intKH = intKH * 0.056;
			break;
	}

	//Calculate CO2
	intPower = 7 - intPH;
	intPower = Math.pow(10, intPower);
	intCO2 = 3 * intKH * intPower;

	//Display results
	document.forms[1].txtCO2.value = intCO2 + " ppm";
}

//-->