planr package Glossary

Here is a domain-focused glossary for the planr R package.

The package is designed to perform classic operations within the scope of Demand and Supply Planning and the Sales & Operations Planning (S&OP) process using tidyverse-compatible data frames.

Core Planning & Inventory Functions

light_proj_inv()

  • Supply Chain Concept: Basic Projected Available Balance (PAB).

  • Description: Calculates basic projected inventories and forward coverage periods for a SKU or group of SKUs over a given time horizon. It does not perform parameter analysis; it simply steps through time using the formula:

\[\text{Projected Inventory}_{t} = \text{Projected Inventory}_{t-1} + \text{Supply Plan}_{t} - \text{Demand}_{t}\]

proj_inv()

  • Supply Chain Concept: Inventory Exception Analysis & Parameterized Projection.

  • Description: An advanced version of light_proj_inv() that projects inventories and coverage, while evaluating the results against targeted thresholds (e.g., Min/Max or Safety Stock metrics). It is used to flag stockouts, under-stocks, and over-stocks for portfolio dashboard reporting.

drp()

  • Supply Chain Concept: Distribution Requirements Planning (DRP) / Replenishment Plan.

  • Description: Generates a time-phased replenishment schedule based on key parameters including Safety Stock Cover (SSCov), Frequency of Supply / Coverage Duration (DRPCovDur), and Minimum Order Quantity (MOQ). It respects a Frozen/Free Horizon (FH) indicator to preserve fixed execution windows.

proj_git()

  • Supply Chain Concept: Goods-In-Transit (GIT) Pipeline Projection.

  • Description: Projects total network inventory by factoring in current open transit pipelines, future planned shipments, and specified Transit Times (\(LT\)).

Demand & Allocation Functions

const_dmd()

  • Supply Chain Concept: Capable-to-Promise (CTP) / Constrained Demand.

  • Description: Evaluates unconstrained demand against projected available inventory and incoming supply to determine the actual volume that can be fulfilled and when it can be delivered.

alloc_dmd()

  • Supply Chain Concept: Fair-Share Allocation.

  • Description: Allocates constrained demand among multiple receiving entities (e.g., subsidiaries, regions, or distributors) based on a “fair-share” percentage ratio of their initial unconstrained requests.

Time Bucket

month_to_week()

  • Supply Chain Concept: Calendarization / Demand Disaggregation (Even Distribution).

  • Description: Splits monthly demand data into weekly buckets by distributing the totals evenly (typically 25% per week) to translate high-level S&OP plans into tactical schedules.

month_to_weekx()

  • Supply Chain Concept: Weighted Calendarization / Profile-Based Disaggregation.

  • Description: Disaggregates monthly demand into weekly buckets utilizing a custom user-defined weight distribution pattern (e.g., to account for historic mid-month dips or end-of-month spikes).

Specialized Extensions

ssl()

  • Supply Chain Concept: Short Shelf Life (SSL) & Obsolescence (SLOB) Risk.

  • Description: Monitors batch/lot expiration profiles against forward demand forecasts to calculate expected inventory write-offs or blocked stocks before they breach Remaining Shelf Life (RSL) limits.

proj_cov()

  • Supply Chain Concept: Days of Cover (DoC) to Volume Translation.

  • Description: Inverts coverage targets back into volumetric inventory units based on forward demand patterns.

Key Parameter Glossary (Function Arguments)

  • DFU: Demand Forecast Unit. The unique key identifier combining product and location (similar to a SKU-Location or Item-Warehouse key).

  • FH: Frozen Horizon. A binary flag (Frozen / Free) that determines if the drp() engine can place new orders or if it must accept the current plan as locked.

  • SSCov: Safety Stock Coverage. The target safety stock expressed as a duration of time (e.g., 2 means maintaining 2 periods of forward demand coverage).

  • DRPCovDur: DRP Coverage Duration. The replenishment cycle frequency (similar to a Fixed Order Period or Economic Order Interval) representing how many periods of demand an order should cover.

  • MOQ: Minimum Order Quantity. The lowest allowable supply order constraint enforced during replenishment runs.