contracts / InterestRateSwap / Calculation / <init>

# <init>

`Calculation(expression: Expression, floatingLegPaymentSchedule: Map<LocalDate, FloatingRatePaymentEvent>, fixedLegPaymentSchedule: Map<LocalDate, FixedRatePaymentEvent>)`

The Calculation data class is "mutable" through out the life of the swap, as in, its the only thing that contains data that will changed from state to state (Recall that the design insists that everything is immutable, so we actually copy / update for each transition)