FDM.3:4.2.1 - Match or adapt an available model

Try an available model against these rules before constructing a new one. Select a contract family by behavior: scheduled principal repayment only at maturity, specified principal installments and equal total installments imply different future calculations. The marketing label “loan” does not decide among them. An optional prepayment is also different from a mandatory amortization installment.

Inspect the chosen model’s definitions, assumptions and event behavior. Check that it can express the actual allocation, calendar and exercise rules. Use it directly when it fits, extend a separable missing behavior when the other meanings remain valid, or retain the unsupported part explicitly. A software default can be used as an explicit assumption; it does not determine the agreement’s meaning. SIE.3 supplies this reuse decision; SIE.4 supplies a qualified correspondence when two representations use different meanings.

For an ACTUS implementation, the useful return is to the chosen contract type’s schedule, state initialization, payoff calculations and state transitions, together with the selected dictionary and implementation edition. Supply the operative terms, a supported starting state and any external observations or scenarios that the model needs. Compare its produced events with the agreement-based construction. A successful sample request establishes execution of that sample; it does not establish the mapping for another contract.