Patterson-LaForge Incremental Part-Period Algorithm

Public class: PattersonLaForgeIncrementalPartPeriodSolver.

Reference:

J. W. Patterson and R. L. LaForge (1985), The Incremental Part-Period Algorithm: An Alternative to EOQ, Journal of Purchasing and Materials Management 21(2), 28-33.

DOI: https://doi.org/10.1111/j.1745-493X.1985.tb00132.x

Rule

For a lot beginning in s, IPPA accumulates the holding cost created by successive future requirements and extends the lot while

\[h\sum_{t=s+1}^{j}(t-s)d_t \le A. \]

The first candidate that would make cumulative incremental holding cost exceed the setup cost starts the next search cycle.

Relationship to PPB

PPB selects the cumulative part-period quantity closest to the economic part-period target. IPPA instead uses a one-sided incremental stopping rule. That difference is preserved explicitly in the public strategies.