def __init__(self, quantity, time_unit='Y'):
Validate.required(quantity, "quantity")
Validate.non_negative(quantity, "quantity")
self.quantity = quantity
Validate.one_of_allowable(time_unit, ['Y', 'M', 'W', 'D'], "time_unit")
self.time_unit = time_unit
def validate_init_values(unit_cost, ordering_cost, holding_rate,
holding_cost, holding_time_unit, shortage_cost):
Validate.required(unit_cost, "unit_cost")
Validate.non_negative(unit_cost, "unit_cost")
Validate.required(ordering_cost, "ordering_cost")
Validate.non_negative(ordering_cost, "ordering_cost")
# accept holding_rate or holding_cost, but not both
# (at least one is required)
Validate.one_only([holding_rate, holding_cost],
["holding_rate", "holding_cost"])
if holding_rate is not None:
Validate.non_negative(holding_rate, "holding_rate")
else:
Validate.non_negative(holding_cost, holding_cost)
Validate.one_of_allowable(holding_time_unit,
RawCosts.supported_time_units,
"holding_time_unit")
Validate.required(shortage_cost, "shortage_cost")
Validate.non_negative(shortage_cost, "shortage_cost")
