static private String getTypeFromUnit(String s){
		
		for (int i = 0; i < weightUnits.length; i++) {
			if (weightUnits[i].unit.equalsIgnoreCase(s) ||
					weightUnits[i].abrv.equalsIgnoreCase(s)) {
				return "weight";
			}
		}
		
		for (int i = 0; i < volUnits.length; i++) {
			if (volUnits[i].unit.equalsIgnoreCase(s) ||
					volUnits[i].abrv.equalsIgnoreCase(s)) {
				return "vol";
			}
		}
		
		for (int i = 0; i < pressureUnits.length; i++) {
			if (pressureUnits[i].unit.equalsIgnoreCase(s) ||
					pressureUnits[i].abrv.equalsIgnoreCase(s)) {
				return "pressure";
			}
		}

		return "undefined";
	}