public void convert(Montant valDep) {
		double val = valDep.getValeur();
                
		Unite unit = valDep.getUnite();
                Conversion conv = unit.getConv();
                
                /* the methods will change depending on the type of conversion
                 * first step of the conversion : from the unit of the beginning
                 * to the standard unit
                 */
		switch (conv.getType()) {
		case ADDITION:
			val = conv.calculAdd(val);
			break;
		case MULTIPLICATION:
			val = conv.calculMul(val);
			break;
		case COMPLEXE:
                        val = conv.calculComplexe(val);
			break;
		default:
			break;
		}
		
                //second step : from the standard unit to the unit of the end
                conv = unite.getConv();
                valeur = conv.getValeur();
		switch (conv.getType()) {
		case ADDITION:
			val = val + valeur;
			break;
		case MULTIPLICATION:
			val = val /valeur;
			break;
		case COMPLEXE:
                        double valeurComp = conv.getValeurComplexe();
			val = val / valeurComp;
			val = val + valeur;
			break;
		default:
			break;
		}
		
                //give the result for the unit that was chosen by the user
		valeur = val;
	}