Heuristics 

Use

You use heuristics to solve specific planning tasks for selected objects (depending on the focus of planning: products, orders, operations, resources or line networks) using a particular planning procedure (algorithm). You are able to use your own heuristics or the heuristics provided by SAP. SAP provides a number of standard algorithms (also referred to as function modules) to solve specific planning tasks. For each algorithm, you are able to vary the settings, thereby defining different heuristics using the same algorithm.

You use heuristics in both interactive planning and during background planning. In the product master for each product, you can define which heuristic is to be used during the production planning run or when executing the product heuristic in interactive planning.

Prerequisites

Features

Standard Heuristics

Several standard heuristics are provided by SAP in the following areas:

These heuristics are mainly lot-sizing procedures whose planning focus is on products. Examples of these heuristics include periodic lot-sizing and purchase order optimization.

These heuristics are scheduling heuristics whose planning focus is on resources and operations. Examples of these heuristics include reduce lead times and resolve backlog.

These heuristics generate planned orders to requirements taking into account the resource capacity for each period. The focus of planning is on resources, line networks and products.

This heuristic optimizes the sequence of configurable products while taking any restrictions into account. The focus of planning is on resources and line networks.

Defining Your Own Heuristics

In APO, you are able to define your own heuristics using the algorithms provided by SAP. You can define heuristics in Customizing for Production Planning and Detailed Scheduling, under Heuristics ® Maintain Heuristics, by entering the algorithm provided by SAP and defining the settings as required.

You are also able to use your own algorithms to create heuristics provided that you integrated the algorithm into the APO System. For more information, see Creating Heuristics Using Your Own Algorithms.

Heuristics for Automatic Planning in a Planning Run

You are able to define a heuristic at product-location level that is to be used for automatic planning during the planning run. On the PP/DS tab of the product master, you can define which heuristic is to be used to plan the product. You can set the Automatic planning in planning run indicator for a product. In this case, the system generates a planning file entry for the product every time a change relevant to planning is made. The products are then planned during the next net change planning run (you set the Planning file entry created indicator on the initial screen) using the heuristic defined in the product master (if you enter the product heuristic on the initial screen of the production planning run).

If you do not set the Planning file entry created indicator, a regenerative planning run will be performed, thereby planning all products in the selection.

If the products are to be planned according to the heuristic maintained in the product master, you use the Product Heuristic. You may, however, perform a net change planning run using a different heuristic.

You can also execute several heuristics on the same products in one planning run. The heuristics are executed in the sequence you enter them on the initial screen. An example of this could be that you perform the SAP001 Schedule sequence heuristic to improve the resource loading and then perform the SAP_PP_007 Move requirements to receipts heuristic to reschedule the top level orders accordingly.

Heuristics in Interactive Planning

You are able to define which heuristics appear in the interactive planning menus of the:

You do this by defining a heuristic profile containing the relevant heuristics in Customizing for Production Planning and Detailed Scheduling, and then by entering the appropriate heuristic profile in the overall profile for the screens. You are then able to start the heuristics in interactive planning by accessing them from the menu.

In the interactive planning screens, you can plan the product according to the heuristic defined in the product master by using the Product Heuristic function, or you can choose another heuristic and vary the parameters for this heuristic by using the Variable Heuristic function. The variable heuristic also allows you to select components for the products that are also to be planned with the heuristic.

For more information, see Heuristics in Interactive Planning.

Planning Run in Simulation Mode

You can execute a production planning run and save the results in a simulation version. This allows to decide at a later point in time whether or not to merge the simulation into the operative planning version.