function powerNumber(userClassesNumber){
	var userClasses = new Array();
	var userClassesNumber = userClassesNumber;
	
	while (userClassesNumber >= 1){
	 var nthPowerOf2 = 1;
	 while(nthPowerOf2 <= userClassesNumber){
	  nthPowerOf2 *= 2;
	 }
	
	 nthPowerOf2 /= 2;
	 userClassesNumber -= nthPowerOf2;
	 userClasses.push(nthPowerOf2);
	}
	return userClasses;
}//end function
//call this function with: return userClasses 
//which returns the array of class numbers
//1=bus self; 2=bus class; 4=essay self; 8=essay class; 16=quiz self; 32=quiz class

//************************************************This needs updating when new modules are added
function powerSelf(userClassesArray){ //input results from powerNumber tells the user is a self directed user 0=NO 1=YES
	var powerSelfTest = 0;
	if(($.inArray(1,userClassesArray)>-1)||($.inArray(4,userClassesArray)>-1)||($.inArray(16,userClassesArray)>-1)){ //check for self directed classes
		powerSelfTest = 1;
	}else{
		powerSelfTest = -1;
	}//end if

	return powerSelfTest;
}//end function

function powerNumberOfClasses(userClassesArray){ //input results from powerNumber tells how many classes have been bought (check if need to ask class/teacher)
	var numberOfClasses = userClassesArray.length; //how many classes have been registered
	return numberOfClasses;
}//end function