Something on the order of 10-20 emails later, I finally got my speaker on the schedule for the undergraduate seminar. I handled most of the arrangements; I’ve been trying to get this scheduled since the beginning of the semester. The speaker is coming next week Wednesday; I think it was long past time!

I just want you to imagine for a second how much frustration is built in to working with someone who requires 10-20 requests and reminders to do a fairly routine and straightforward job of putting a speaker on a schedule, reserving a room and designating a time. It would have been easier if I had just had a special seminar for this speaker, arranging the room and time myself.

Needless to say, I am not going to work with that undergraduate seminar organizer again any time soon if I can avoid it. Of course, my boss may dictate that I can’t avoid it. It’s sad, because I have another (good) speaker lined up for that seminar, and I’m not willing to put either of us through this nonsense.

———

I feel tense and angry. Describing the interactions earlier today, I’ve said I had to throw a hissy fit in order to get the job done. I feel like a real bitch.

I look at those judgments. I got justifiably angry after so many repeated requests. “I threw a hissy fit,” really? I think everyone is within their rights to get angry and frustrated under those circumstances. Having to make repeated strident requests of someone to please do their job … it feels bitchy, but is that bitchy? It is the helplessness and frustration of having to work with someone who is not working.

Since I am female and I am angry and frustrated, even I label myself as bitchy.

I think men (and other women) deemed special and important find those of us deemed less special and less important (in part because of our gender) easy to ignore and blow off. Too often we get labeled as bitchy when someone blow us off and we don’t go along with it. And, sadly, even I cooperate with this and label myself as bitchy.

I feel bitchy.

But I think I was justifiably angry. Very angry. And very justified.

———

Today one of the “participation points” opportunities in class was to explain the difference between two Matlab calls to the differential equation solver `ode45()`. The function, `ode45()`, solves differential equations of the form

$$\dfrac{d\mathbf{x}}{dt} = \mathbf{f}(t,\mathbf{x})$$

where \(\mathbf{x}\) can be a vector and \(t\) is your independent variable (usually time). The syntax to `ode45()` is `ode45( function, time span, initial condition)`. The function is the \(\mathbf{f}(t,\mathbf{x})\) in the differential equation. The time span can be given two different ways. I put the following two sets of commands up on the board with a request to explain what each did.

`tspan = [0 50];
[t u] = ode45(@lorenz, tspan, u0);`

or

` tspan = 0:0.01:50;
[t u] = ode45(@lorenz, tspan, u0);`

To you the difference may not be obvious (although I hope you could easily Just Ask Google). Possibly it is not obvious to the students either, but I know they are about to get bitten by this in some code they have to write. My students have been instructed to Just Ask Google, I think everyone in the class can figure this out.

Recall that a solution to a differential equation is a function \(\mathbf{x}(t)\). Matlab can’t give you back a function, it gives you back a vector `t` with the time values and a matrix `u` where the rows are the components of \(\mathbf{x}\) evaluated at the corresponding time in `t`

If I give only the start time and end time, `tspan = [0 50]`, Matlab will decide where to evaluate my function \(\mathbf{x}(t)\) in between those points. If I dictate the points in the middle of the range, then Matlab will evaluate \(\mathbf{x}(t)\) where I tell it to. This is useful, since otherwise two solutions to a differential equation may be evaluated at different points, and you may wish to compare them by, for example, finding the distance between them.

Several students found out in office hours that paying attention in class is actually worth while. Running into precisely this problem, I first asked if they remembered what we discussed about this in class. Then I asked if they could bring out their notes from class (notes?!?). Then I had them pull out a piece of paper and wrote out the two commands that had been on the board and I asked again what was the difference. I then reinforced the idea that I really do try to do useful things in class and I would really appreciate it if they paid attention and took notes.

I managed all of this with a fairly even temper.

My patience was tested further by a student unable to solve the differential equation

$$\frac{dx}{dt} = x$$

No signs of intelligence whatsoever after I suggested separation of variables. A differential equations course **is** a prerequisite for this class, and “I don’t remember anything!” is not much of an excuse. I bitterly blame his differential equations instructor for lax standards, and the sad thing is, she’s the person I see in the mirror every morning as I brush my teeth!

Math formulas courtesy of MathJax, which is awesome and you should check it out.