student-written image descriptions need quality control

[Alex-Jordan]

I think that recently some students wrote descriptions of images. But it's come to my attention that these are frequently quite bad, mathematically. For example:

The "domain" is not 0 to 3. Of course the student author of this was trying to say what the x-interval of the viewing window was.

Then there are nonsensical things like "0 ≥ x < 1".

And then the actual claim that the "graph has a downward curve" over what is implied to be [0,1] is poorly worded. I guess that means it's concave down there (at a point at which student readers have not learned concavity) but I initially read that as "decreasing".

My last nitpick on this one is with the "graph" being undefined at x=1 instead of the function.

At first I encouraged a colleague to file an issue for an individual image, but it seems that there are many image descriptions with this kind of concern.

Just reporting! I know that image descriptions are important and it's progress to at least have something there to fix.

[sean-fitzpatrick]

Ugh. I'm sorry that this one got past me.

I was doing some quality control on these, and reviewing before accepting a PR. But some students were better than others, and occasionally I missed mistakes.
(This one is really bad, though. I'm annoyed that I missed it.)

If someone wants to open a PR with corrections, I would be very happy to receive it.

[sean-fitzpatrick]

I think there will be some sections with several bad descriptions, since students worked by section. If this section is particularly bad I can prioritize fixing it.

[Alex-Jordan]

I haven't done a thorough inspection. But it seemed like the section 1.1 descriptions are like this (and that's as far as I looked). Since it is the first section of the book, it gives an impression.

I'll check in with the instructor who reported this and ask if he'd like to write descriptions.

[sean-fitzpatrick]

I might have time to review the descriptions in Chapter 1. It'll mean another reason for me to procrastinate on Jason's documentation push, though. :-)

[sean-fitzpatrick]

Oh good lord, Section 1.1 is awful. I must have been having a bad day when I approved these.
The use of "equation" instead of "function" is making me cringe.

I've fixed the first 8 (out of 27), and have to run to class. More to come.

I am going to resist going back to find out who wrote this.

[sean-fitzpatrick]

Unrelated (aside from me seeing it while fixing these descriptions), but also strange, and I'm not sure why it changed:

In this figure, the graph and the secant line are plotted using \addplot+. The plot cycle defined in our image preamble should have the secant line as a red, dotted line (secondcurvestyle) but it is solid blue (firstcurvestyle).

[sean-fitzpatrick]

OK, I figured out how I messed up some of the figures: the style "infinite" is defined as firstcurvestyle, {Kite}-{Kite}.

I need to remove firstcurvestyle from all of the style commands that are there to change whether or not the ends are decorated with arrow heads.

[sean-fitzpatrick]

Work started in #318