STEM help / Calculation framework

10.3.17 Functions

The original STEM methodology for the supply side of a network was built around the concept of logical Functions representing the different roles played by different physical pieces of equipment, with one or more Resources within each Function capturing the physical parameters and costs relating to a specific item. This is the fundamental basis for modelling technology migration, through the automatic take-up of capacity of one Resource as another in the same Function is either replaced or removed.

However, in many models, technology migration is limited to a few Functions, if any. The remaining Resources cannot generally be placed in one Function, as this would imply that capacity is transferable, i.e., that capacity from one Resource could be replaced with capacity from another. So the original methodology demanded separate Functions for the remaining Resources in a model, slowing the model-building process and cluttering views with ‘dummy’ Functions.

Now this hierarchy is optional, and Resources can be created at will without the need for a ‘parent’ Function. Instead, suitably compatible Resources can be grouped together as required when the Function model is required.

Creating an optional Function

In order to create a Function to group two or more Resources:

  1. Select the compatible Resources and then click the Function button on the toolbar, or press <Ctrl+Shift+F>. A new Function is created, automatically linked to the previously selected Resources.

Alternatively, you can create the Function first, and then drag individual Resources into the Function while pressing <Ctrl>, or you can select Insert Element into List from the Function/Capacity Edit menu and then choose which resources you want to associate with that Function. Resources without a Function will behave just as though they were separately associated with a default Function element.

Function interface to dialogs

The removal of the rigid Function hierarchy enables a more streamlined user interface for Resource Requirements. The original Resource Requirement dialog for a Function has been replaced by an interface which caters for an individual Resource as its standard form – see 10.3.27 Resource requirements.


The need to supply capacity of a Function at more than one site is described by the Deployment data for that Function – 10.3.18 Locations and deployment.


       Buy SSL

© Implied Logic Limited