function show_window_content(w,h,link,name,scroll) {
	leftPos = 0;
	topPos = 0;
	var n= name;
	if (screen) {
		leftPos=(screen.width-w)/2;topPos=(screen.height-h)/2;		
	}
	window.open (link,n,'height='+h+',width='+w+',left='+leftPos+',top='+topPos+',status=yes,toolbar=yes,menubar=yes,location=no,resizable=yes,scrollbars='+scroll);
}					
function calculate1()
{	
	validateAmount('od',0);
	validateAmount('cd',0);
	validateAmount('cf',0);
	
	document.getElementById("totc").value = eval(document.getElementById("od").value) + eval(document.getElementById("cd").value) + eval(document.getElementById("cf").value);
	document.getElementById("totc1").value = document.getElementById("totc").value;
	calculate3();
	return true;
}
function calculate2()
{
	validateAmount('ale',0);
	validateAmount('sthp',0);
	validateAmount('sssb',0);
	validateAmount('ii',0);
	validateAmount('ny',0);	
	document.getElementById("totle").value = 
		(eval(document.getElementById("ale").value) - 
			(eval(document.getElementById("sthp").value) + 
			 eval(document.getElementById("sssb").value) + 
			 eval(document.getElementById("ii").value)
			 )
		 ) * eval(document.getElementById("ny").value);
	calculate3();
}
function calculate3()
{
	document.getElementById("tli").value = eval(document.getElementById("totc1").value) + eval(document.getElementById("totle").value);
}
function validateAmount(field,def) {
	var re = /[^0-9.]/i;
	var fld, val;
		
	//fld = eval("document.steps."+field);
	fld = document.getElementById(field);
	val = fld.value;
	if (val == "") {
		fld.value = 0;
		return true;
	}
		
	if (re.test(val)) {												
		fld.value = def;			
		return true;
	}
	return true;
}