Video annotation of the J labs (including commentary and animation) can provide an extra dimension to the learner. If you haven’t yet used labs, you simply must open a J session, open the ‘Studio’ menu and select ‘Labs’. Using “An Idiosyncratic Introduction to J”, the lab written by Roger Hui, we’ll develop ways video can be incorporated into the JHS environment to create an effective learning tool. Let’s look at the first lesson of the lab.
───────────────────────────────────────────────────────────── Lab: An Idiosyncratic Introduction to J Author: Roger Hui To advance the lab, select menu Studio|Advance or the corresponding shortcut. ── (1 of 15) Introduction ────────────────────────────────── J is executable mathematical notation. ) 2 + 3 5 x=: 2 y=: 3 x + y 5
This is pretty straight forward, but like J, it is terse to the point of impeding communication. Examples of how the language works follow the one line introduction. In this lesson I think that the best use of the video annotation is to introduce the lab and then emphasize the importance of that first line. Following is a first draft for the video script.
This introductory lab was written by Roger Hui, one of the originators of the J language. His idiosyncratic approach moves from simple foundations to sophisticated concepts in just 15 lessons. This video commentary is meant to showcase the subtleties of the lab. The long button below advances lab lessons and video together; the numbered buttons allow random access of the videos (but not the lab lessons). The window to the left is a working J session and allows you to enter any J statements you wish interactively.
The first lesson begins with the statement “J is executable, mathematical notation”. This simple sentence holds great power. We can see in the examples that follow it, by typing the expression, 2 + 3 and pressing return we get the response 5, and because J is also a mathematical notation, using J to express mathematical ideas makes mathematics machine executable. Take a moment to consider the opportunity that J provides through executable, mathematical notation. A mathematical idea expressed in J notation can be executed with the press of a button; you now have the keys to a math laboratory.
So, that’s about it for now. I look forward to comments on what you’ve seen.