## Maybe I’m Starting to Catch On

And on the other hand, maybe not.

As we approach the end of Week 3, I was just starting to feel a little bit comfortable – not totally on top of things, but at least less like I’ve got no business being where I am, doing what I’m doing. My first outing in CMJ 103 went well, I’ve got a topic in hand for my second speech in a couple of weeks (and I’m looking forward to doing some research in the process of putting it together), and attending the lecture sessions in MAT 122 was *definitely* the right call; I feel almost like I might know what I’m doing when I work on that material now.

Even in ECE 101, I was starting to feel like it was coming together for me. Today’s class period was set aside for recitation; it was optional, but I went anyway, and another guy and I ended up scribbling resistive circuits on the blackboard and having a grand old time figuring out whether things were in parallel or series (it’s sometimes hard to tell from the schematic). I’m not going to puff out my chest and say I’m on top of the material, but I’m *keeping up;* I don’t feel like the class is out ahead of me, as it were. Pilots talk about being “behind the airplane”; that’s the way I’ve been feeling, and this morning that sensation was starting to ebb.

Until I turned up for our ECE 101 lab period this afternoon, and we started getting our introduction to MATLAB.

I should explain at this point that MATLAB is… well, to call it a math program is a bit like saying that the Pacific Ocean is “a body of water”, but it’ll have to suffice for our purposes. In ECE 101 we’re using it primarily for graphing and working out the answers to hideously abstruse simultaneous equations. I first encountered it back in 1991, when, like everything else on WPI’s computers at the time, it was a powerful but hilariously primitive command-line tool. (Nowadays it’s a powerful but hilariously primitive command-line tool wrapped up in some X Window tinsel. But not very much of it.)

And here’s where the wheels started to come off the bus a little bit. The MAT in MATLAB, which is one of those Navy-style partial-word acronyms like COMSUBLANT, doesn’t stand for “math”; it stands for “matrix”. It assumes that any set of variables you feed it represent a mathematical matrix and operates upon them accordingly. Thus, to solve the aforementioned simultaneous equations (which, in the example we were using, were connected with something called the Kirchhoff current law), Andy explained, you have to use said equations to construct a set of matrices and then goad MATLAB into solving them for you.

Several of my classmates, at the workstations around me, had “oh yeah” moments, and a lively discussion of the ins and outs of pitting matrices against each other ensued. I sat among them having one of those Hitchcock dolly zoom moments, and when a decent conversational lull occurred, I hesitantly interjected,

“I have no idea what you guys are talking about now.”

Andy gave me a blank look. “Matrix algebra.”

“Which is… ?”

“High school stuff. Algebra II, probably.”

And here’s the thing. I know Algebra II was a long time ago for me. I took it in my sophomore year of high school, which was several years before most of my classmates were even born. But even so, I don’t remember *a single thing* about the topic of “matrix algebra”. I sincerely don’t believe we covered it. Maybe it was one of those things that was near the end of the book and we just didn’t get to it before the end of the school year; that happened a lot at Stearns High. Maybe it hadn’t been invented yet. Maybe we just didn’t cover it. I don’t know. But I’m fairly sure that I was never exposed to it. If I was, I’ve managed to forget it *so completely* that I didn’t even remember the *term*.

Either way, it may not matter, because in the context of ECE 101 it appears I don’t actually have to know how it works, just how to plug it into MATLAB, which I’m now reasonably confident I can do. But that was the first moment in which I’ve run up against an actual *hole – *not just a fuzzy spot but a genuine void – in the foreknowledge the curriculum assumes I have. This doesn’t interact well with that growing sense of belonging-there I was talking about at the beginning…

Oh good lord they’re making you use MATLAB? In a 101 course? I mean, I love me some MATLAB (or I did six or seven years ago back when I was still in a vaguely scientific field), but holy crap is that a complex piece of software to sic on freshmen.

OTOH, at least you’re not having my MATH 115 experience, which had us using Mathematica but only through some weird-ass add-on to Mathematica that the professor had written. This resulted in the assignments being about as confusing as they would have been had they been in Mathematica proper (perhaps more, given the relative scarcity of documentation for the not-quite-Mathematica product, we could have at least googled for Mathematica instructions), and also failed to teach us any useful skills, since nobody uses the professor’s not-quite-Mathematica add-on. I’m still mildly bitter about this a good 14 years later. At least if you learn Matlab you’ll have a useful skill! And it really is neat, I wrote some seriously complex and spiffy simulations using it back in the day.

Yeah, I’m pretty sure what we’re doing with MATLAB in ECE 101 is the equivalent of using a full-featured graphing scientific calculator to do your 1040EZ (in fact, I think my TI-89Ti actually has a stripped-down version of the MATLAB kernel in it), but it’s a pretty honkin’ piece of software. We’re dipping our toes in it in 101 because the ECE department uses it for all kinds of stuff as the curriculum progresses. The department’s had a site license for it since sometime in the ’80s, so it’s kind of part of the upholstery now.

I’m starting to get the idea behind ECE 101; it’s not so much about the actual material we’re covering (we’ll come back to most of it in greater detail in later course) as it is about giving us a taste of the discipline and, most importantly, getting us thinking like engineers. In the old days, UMaine engineering students didn’t touch anything directly connected to their disciplines until sophomore year – freshman year was entirely given over to general-ed prereqs and basic college stuff. A few years ago the College of Engineering realized that they were getting a lot of people dropping the program after freshman year because they were frustrated by that long lead time, so they developed the 101 “concept courses” for each discipline in hopes of getting more engagement going on in year one.

Don’t freak too much. Matrix algebra is not generally covered all that much in high school courses, the people you talked to might have been at the advanced end of the overall distribution (i.e. my high school had two years of Physics available, but it’s not like Physics II is “standard high school stuff”).

As you note, you don’t really need to understand matrices to use MATLAB the way your course is set up. Probably the main thing you need to know is that matrix multiplication doesn’t commute: A times B is not generally the same as B times A (although there is a special class of matrices where it is). So order matters.

Not too related to MATLAB, but have you looked at downloading EE Pro and EE200 for your TI89Ti yet?

I grabbed ME Pro and it brings me back to those days… makes me want to break out the heat transfer and thermo/fluid dynamics books again…

Plus, I think the TI89Ti can handle matrices/linear algebra (aka Mattresses and Little Gerbils back at WPI). Wish I had it back then.

Mine came with EEpro already on it; I don’t know how to do anything it does yet, but I’m sure it’ll be handy someday. Andy claims it does do matrices, in the same syntax as MATLAB requires. He’s a bit of a TI-89 wonk; one of the first things he said in the class was something to the effect of, “Do you have your TI-89 yet? You’ll need one if you’re going to be a grown-up engineer.”