Gold star summary for November

Amazingly enough, lorne didn't win this month. Instead it was gliderguider with a score of 6-5.

• 23 Nov 07 - lorne - Don't Stop Me Now by Queen
• 11 Nov 07 - gliderguider - Time by Pink Floyd
• 10 Nov 07 - lorne - Egobrain by System of a Down
• 08 Nov 07 - lorne - Thetawaves by System of a Down
• 07 Nov 07 - lorne - Time by Pink Floyd
• 06 Nov 07 - gliderguider - Comfortably Numb by Pink Floyd
• 05 Nov 07 - gliderguider - Bubbles by System of a Down
• 04 Nov 07 - gliderguider - Jet Pilot by System of a Down
• 03 Nov 07 - gliderguider - Under Pressure by Queen
• 02 Nov 07 - lorne - The Thin Ice by Pink Floyd
• 01 Nov 07 - gliderguider - Headlong by Queen

Turning inside out

I got an A.

w00t :-D :-D :-D

The same in a relative way

And here, finally, is question 8.

This question went really well. It was the one I worried about most and studied for right up to the minute when I went down to the exam room. In the event it went like a dream - it followed the process we'd learned in class exactly without any tricksy deviations, and my memory didn't fail me at the moment of crisis. I know that my process was correct, regardless of mechanical errors, and that's the most important thing.

The hint at the bottom surprised me, though. Firstly that we got a hint at all [this is 300-level!], but secondly - why does it give the formulae for a sine series, when I quite clearly got a cosine series out of my workings? Unless I can be bothered waiting two months to get the paper back, I'll never know whether it was me or the hint that was in error.

Didn't quite finish part (e), as you can tell. I started it so near to the end of the exam that I kept pausing after each line of working to see if we would be stopped yet. In the end I did manage to lay down my pen right in the middle of a line - so the markers can see that the last line on the page wasn't my intended final answer. I did know that it could be simplified further sir, I just didn't have time to do it.

The results should be out any day now. Or sometime within the next week. Or two...

For land, for land

Here's question 7, the worst one of the exam for me. (a) was fine, (b) was fine, the last two parts weren't fine at all. I hadn't studied those parts of Peter's section in detail, so I didn't waste too much time on them. By this stage I think I was nearly 30 minutes behind time, so it didn't really distress me to have to leave something out.

The senses collect undeniable data

Question 5 went pretty well too, apart from the aforementioned difficulty with the complex eigenvectors for part (b). Halfway through my attack on them I actually wrote the following in my paper:

Is λ really an eigenvalue?
(Workings)
Yes, it is.
So why can't I find the eigenvector?

Unfortunately I forgot to cross this out when I'd finished, but I don't think Chris will mind.

The bit of highlight beside part (b) means that I finished the thinky part of that question, but didn't quite finish simplifying it. There was a matrix full of horrid long expressions in cis, and I knew full well that I could simplify it down to a matrix with purely real entries, but didn't have time to actually do so.

Some time after the exam I realised I'd named the types of the critical points, but hadn't mentioned their stability or otherwise. This was probably important. Darn.

Tired of lying in the sunshine

The momentarily working Blogger uploader brings you question 4!

As you can see, I never got to the last six marks [because of time]. I did write down which directions the arrows would have had if I'd had time to draw the diagram, though. I don't think I even attempted to work out the time limit to infinity, although I probably should have done, because it wouldn't have taken all that long.

Coming through in waves

First of all, here's my proof that the function suggested by gliderguider yesterday does indeed answer question 1(g) satisfactorily:

And here's question 2. This was my favourite question. The last part took me hours the first time I did it back in assignment 3, but since then I've gone through the same process so many times that I hardly needed to watch my pen move. [Functions which have this property make good projections for cartography and suchlike.]

Seeing you believing

Archiving things is good. Here's question 1. I highlighted the two marks at the end to indicate that I never got to that bit. Part f was interesting; I had to resort to L'Hopital's rule, to my disgust.

The source of all creation

It was better than I expected, and it was also good. I did 82% of the paper, which included having a shot at all six questions. However time constraints forced me to skip a total of 18 marks in dribs and drabs all over the exam, which meant I effectively did only five questions.

I lost 15 minutes trying to find a complex eigenvector [it's such an easy process that I just couldn't bear to leave it undone even though it was taking ages], but I made up most of that time on the last question, which was much, much easier than expected. The first question of Peter's section threw me a bit, but I'd expected that.

For those readers who also did the exam: I chose questions 1, 2, 4, 5, 7 and 8. The best was question 2 on the Frechet derivative. The worst was question 7 on some multivariate theory that I hadn't studied.

All things considered, I might get an A-!

This is our last dance

Arrived at ground zero 90 minutes early. Hid. Hiding place was not that effective - a random classmate came up and asked me a question a minute ago. It's much easier to hide ahead of weekday exams, when the campus is open and you don't need to swipe through hundreds of doors to get anywhere. [My usual technique is to wait outside an exam room at the opposite end of campus to my own; today I'm in a comp lab.] I don't go down to the exam room until such time as most of the class will be already seated - I don't want to talk to anyone.

I can now do Fourier series and integrate by parts, and separate variables and find non-trivial solutions, and I can do the JCF thing for 2×2 matrices. [Chris hasn't previously put 3×3 ones in the exam, and I'm relying on him to have stuck with that this year.] I've memorised all the definitions I need to know, although it might take a minute under pressure to recall that "hyperbolic" means the derivative matrix has no pure imaginary eigenvalues. I have a calculator, a scarf, three pens, and some hayfever pills. I've even remembered to have lunch.

My biggest challenge now, as with any math exam, is not freaking out.

If a crack in the ice appears

22 hours to go. We get a choice of questions in this exam - two of three questions from each of three sections. I have a few things to try and avoid in each section. In ascending order of horribleness:

• Section A
• Lagrange multipliers (come on, I've only got three hours)
• Section B
• Lyapunov functions (as above)
• Section C
• Fourier series (you want me to memorise what and integrate how?)
• Dirichlet boundary conditions (come on, I've still only got three hours)

I also have a few things that I need to look up in the next 22 hours. How to do the Jordon Canonical Form thing for LHCC systems. How to integrate by parts. How to expand a Fourier series - because I should know it and it really isn't that hard.

Am I ready? When exams are concerned, I'm never ready.

Ain't no stopping and there's nothing you can do about it

The worst part about studying is when you've just started enjoying it and you really want to do it, but for some reason you don't, like there's something else you have to do first - nothing very major, just a little thing like making a phone call or doing some laundry - and then suddenly it's midday and you haven't studied yet, and a sort of pseudo-depression sets in and you spend the afternoon reading some junk novel or other and then another day is over and wasted and you sit down and wonder what the point of it all might be.

I'm having a ball when I do get around to doing some maths, but in between I worry a lot about time. Two days to go now.

Gold star summary for October

This month was a tie between gliderguider and lorne. They each got three gold stars.

• 27 Oct 07 - gliderguider - Terrapin by Syd Barrett
• 25 Oct 07 - lorne - Chic 'n' Stu by System of a Down
• 20 Oct 07 - lorne - Boom! by System of a Down
• 14 Oct 07 - gliderguider - Brain Damage by Pink Floyd
• 11 Oct 07 - lorne - Toxicity by System of a Down
• 02 Oct 07 - gliderguider - Nobody Home by Pink Floyd

The move about is all we do

Despite the world's best efforts to the contrary, good maths continues to happen. I've revised the first four weeks of MATH 301 in detail and also solved a silly little puzzle that's been occupying me on and off for several weeks. At the same time, Hawking's commentary on Euclid is taking my understanding of geometry to whole new levels, which is a pleasant way to pass the time.

My current revision method is one almost guaranteed to drive me around the bend sooner or later - I'm LaTeXing all the key parts of my notes. The idea is that the focused concentration required to get a proof looking nice in LaTeX should help to get the material embedded in my mind. [More so than regular note-taking, that is.]

I don't want to spend too much time on this though, so I'll probably just do the first six weeks and then get on with old exam questions.

This post title isn't really from the Floyd at all. Why, then, have I tagged it as such? ;)

Mushrooms, olives, chives

Picked up assignment 10 on Tuesday. I got 15/40, which is exactly the passing mark for that assignment; of the questions I had time to attempt, my score was a respectable 15/17. This means I've passed all the assignments and have a full 10 assignment marks, so I have to work 17% less hard to pass the course than I would have otherwise.

To be specific, my internal mark is 35% of a possible 40%, meaning I need to score 67% in the exam to get any sort of A, or 25% to pass. It's good to be able to go into an exam knowing that sort of thing.

Here is a [greatly shrunken] graph of my assignment marks. The pink line is the average. Just ignore the last data point :-P

As for study, I'm trying, but my Euclid reading is very interesting indeed.

All your crooked pictures looking good

The QUAN exam is over. I can start playing again!

I picked up assignment 9 when I was on campus the other day - got 38/40. Assignment 10 landed at the School office just a few minutes after I left, so I'll pick that up next week. Peter sent out an email saying the pass mark for assignment 10 is 15/40 rather than the usual 20/40, so he must have noticed about the last assignment being rather excessively long.

Someone gave me the awesomest levelling-up present recently. My spare time is now being filled with Euclid :-D

The lunatic is on the grass

The trimester ended sometime in the last few days, I think. Hard to say; I was too busy trying to stay awake to pay much attention. There was a lecture on Sturm-Liouville thingies, and Bex gave me a bottle of wine, which was a very nice surprise.

I had to hand in assignment 10 less than 50% done. No sooner was it in the box than Peter announced he didn't mind if we saved it till Monday. On reflection, this probably wouldn't have made any difference even if I hadn't already handed it in; there were much more important things to do this weekend.

The QUAN exam is in less than a week, so I won't do any more math until that's over.

Disorder, disorder, disorder

Here is a summary of the last three weeks of MATH 301.

1. Ooh look, a higher-order DE in more than one variable!
2. Hmm, how to solve?
3. Separation of variables
4. How exciting, a list of ODEs which all contain the constant k.
5. What could k be? Positive, negative or zero?
6. Furious investigation of the value of k, followed by application of boundary conditions
7. The only nontrivial solutions for the first ODE come from a particular value of k, and here it is.
8. Let's put that value of k into the other ODEs.
9. Solution sequence!
10. Are there any ugly-looking [inhomogeneous] boundary conditions?
11. Messing around with Fourier series to find a sum or series of the solution sequence which satisfies the ugly BCs
12. Solution!
13. What happened to the last four hours of my life?
14. Repeat twice daily for the next 20 days
15. Discover you've actually been doing linear algebra all along, and it would have been much quicker if you'd known that at the start

Today I attended a Meeting and also visited Rob The Graduate Studies Coordinator, both of which made me feel better about things in general and next year in particular. There are still exams to get through, though, and I'm tired.

Tonight I'll probably be up all night, and I'll probably be lucky to get half the assignment done in that time. It's a real beauty this week - must be Peter's idea of a going-away present.

Nothing is very much fun anymore

Still alive, kinda. One week of lectures to go. Got 27/30 for assignment 8 and 25/30 for the test. I'm really annoyed with that test mark - it reflects a certain overconfidence about some questions, which is something I thought I'd grown out of.

Assignment 9 made it into the box okay yesterday, although not without causing some stress for the people who were around me while I was finishing it. [I'm not a friendly person when under pressure. I wish I was. I'm working on it.]

On Thursday I told Chris my dreams and he told me some facts about the real world which I would have been happier not knowing. Suddenly I'm not going anywhere and my favourite activities are a waste of time.

"The child is grown" was a close second for the title of this post.

Got a strong urge to fly

This morning I attended a tutorial, with Bex and about six others. Much chalk was ground to dust by the Fouriers workings of our brains. I see new approaches to a couple of the assignment questions now, although I'm no happier about Fourier series than I was yesterday. Later I started making a few Maple plots for question 1, but I got rather hijacked by confusion about the sum-to-product trig formulae [either I've done something wrong, or Maple 11 has lost the ability which Maple 9 had to simplify a sum to a product automatically].

Excitement for the day: Bought a new backpack. Emailed Chris about Plan B.