function getCheckedIndex(radioButton){
	for(var i=0;i<radioButton.length;i++){
		if(radioButton[i].checked)break
	}
	return(i)
}

function getSelectedIdex(ctrl){
	
  	var ind=ctrl.options[ctrl.selectedIndex].value;
	
	return (ind)

}

function doCalc(myForm){
	
	var male=(myForm.mv[0].checked==true)
	var weight=myForm.gewicht.value
	//var factor=1.5

	var control = myForm.activiteit;
	var toeslagFactor=control.options[control.selectedIndex].value;
	
	var ctrl = myForm.tijdsduur;
	var tijdFactor=ctrl.options[ctrl.selectedIndex].value;
		



	/* error checks:	*/
	
	if(toeslagFactor==""){
		alert("Selecteer een activiteit!")
		myForm.activiteit.value=""
		myForm.activiteit.focus()
		return false
	}

	if(weight<20 || weight>300){
		alert("Vul uw gewicht in kg in!")
		myForm.gewicht.value=""
		myForm.gewicht.focus()
		return false
	}
	

	var cal=0
	if(male){
		cal=(weight*tijdFactor)*toeslagFactor
	}
	else{
		cal=((0.9*weight)*tijdFactor)*toeslagFactor
	}
window.status=cal	
	myForm.calorieen.value=Math.round(cal)
	return(cal)
	
}

function getSearchStr(){
	var str=location.search
	if(str=="")
		return
	
	str=str.substring(str.indexOf("?")+1,str.length)
	var arr=str.split("&")
	
	for(var i=0;i<arr.length;i++){
		if(arr[i].indexOf("l=") ==0)
			document.form1.lengte.value=arr[i].substring(2,arr[i].length)
		if(arr[i].indexOf("w=") ==0)
			document.form1.gewicht.value=arr[i].substring(2,arr[i].length)
			}
}