Dec 10, 2005

Today's Saturday Explorations class is all about programming. The students begin with an overview of the material that they learned in the previous week, AgentSheets®. They explained how they were able to create agents and have their agents interact with other agents on the screen. Jonathan Stuart-Moore and Monte Evans, two staff members at Shodor, explain how agent-based modeling is similar to programming. The students today will be learning how to program using a language called PERL, Practical Extraction and Report Language.

But before learning PERL, Monte asks the class to explain how to toast a bagel with cream cheese. The students reply that this task is very trivial and begin to dictate the instructions aloud. Jonathan divides the class into two separate groups and he gives each group a marker to write their set of instructions on the board. Each group writes their detailed on the board and waits for further validation from the Kari-tron 6000. Kari Wouk, another staff member at Shodor, serves as the bagel-programming validation machine. She reads the groups code and replies "Does not compute" and leaves the room. The explorers, displaying a puzzling look wonder why Kari does not accept their instructions. This is because Jonathan and Monte have forgotten to give the explorers the syntax, language that the computer understands, to the explorers. Using this new syntax, the explorers re-write their code and the Kari-ton 6000 once again tries to validate it. After several attempts, the teams finally get it right and are given the ability to make their own bagels to eat.

After the explorers return from break, Monte and Jonathan begin their session on PERL. The explorers learn all about different commands that PERL understands, including things called array and variables. The students ask several questions trying to understand how to make these PERL commands work correctly. For instance, when learning how stacks work, Jonathan uses an analogy of the stack of tray in a cafeteria lunch line: where the first tray that goes in is the last tray that comes out. Afterwards the students attempt to write their first PERL program, a shopping cart. They determine that there are several interesting and challenging features to programming, but overall it is quite enjoyable.