function field(key, value)
{
	if(key != null && value == null)
	{
		if(document.getElementById(key).value == "")
		{
			return 0;
		}
		
		return document.getElementById(key).value;
	}
	else if(key != null && value != null)
	{
		document.getElementById(key).value = value;
		
		return field(key);
	}
}

function floatField(key, value)
{
	if(key != null && value == null)
	{
		return parseFloat(field(key));
	}
	else if(key != null && value != null)
	{
		return parseFloat(field(key, parseFloat(value)));
	}
}

function boolField(key, value)
{
	if(key != null && value == null)
	{
		return document.getElementById(key).checked;
	}
	else if(key != null && value != null)
	{
		document.getElementById(key).checked = value;
		
		return boolField(key);
	}
}