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Lab 2A: An introductory tutorial

This introductory lab is a basic tutorial on Empirical Modelling. It is derived from a student coursework submission from 2007.

The lab introduces the EDEN interpreter. Applications of EDEN will be demonstrated in many lectures. In this lab, the use of EDEN is scaffolded by the Empirical Modelling Presentation Environment (EMPE). The EMPE will feature in the construal comprehension exercise that is the first assignment for MSc students.

Getting Started

The resources for the CS405 labs are in the public directory /dcs/emp/empublic/teaching/cs405-2013. This will contain subdirectories for the labs as they are developed during the term.

To access the resources for Lab 2A, you should open up a shell window (you can do this by pressing Alt+F2 and typing "konsole" into the search box) and copy the following into it:

cd ~empublic/teaching/cs405-2012/lab1

To bring up the EMPE, use the following command to execute the shell script in this directory:

./execlab1

You may need to be a little patient, as the EMPE takes a while to load, and it may appear that nothing is happening. Once the environment is loaded, you should be able to follow the tutorial by reading the presentation. In this tutorial, you are interacting with a spreadsheet-style network of definitions of simple geometric objects (such as points, lines and circles) that are intended to represent the floor plan of a room with some simple objects of furniture. You can navigate from slide to slide using the 'Next' and 'Previous' buttons at the bottom right of the screen. Buttons within the presentation enable you to enter input into the EDEN interpreter either for direct execution or for editing in the input window on the bottom left. Each input modifies the network of definitions either by redefining an existing observable, or introducing a new definition.

Further study

The full script of the room floorplan can be found in the file room.d in the lab1 directory. To explore this script in a more open-ended fashion, you can interpret this script without using the EMPE wrapper. For this purpose, you can execute the foillowing command within the lab1 directory:

~empublic/bin/tkeden room.d

More information about executing EDEN in this way can be found in this labsheet, subject to substituting cs405-0809 for cs405 in the directory names cited there. The tutorial in effect presents answers to the labsheet.

You can also use the EMPE to extend the introductory tutorial. For this purpose, you make use of the 'Edit slide'. 'Add slide' and 'Copy Definitions' buttons on the interface. For more details, see Using the EMPE. For a brief introduction to the EMPE written in the EMPE itself, execute the following command in the lab1 directory:

./execEMPE