Reasonably regular visitors to the site will know that I’m now in my fourth year of a mathematics degree at the University of Warwick. A good sized chunk of this year’s credit is given for a dissertation on a subject of our choosing; we can either choose to write about some kind of mathematics in action (the MIA project) or a research project, which involves finding a supervisor willing to sponsor you on a topic of your choosing.

As I’m hoping to continue further with my education, possibly going onto a PhD, I chose to do a research project. This post is basically an entry describing my particular woes finding an appropriate project, and it’s quite long; unless you’re interested, it’s best not to continue further!

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Continue reading “Is it really this hard to find a dissertation?”…

3:53 pm | Posted in Maths, Project, Whining | No Comments »

Firstly, I’m sorry about the lack of updates. I’ve been really up to my neck in work and preparations for various things and university. I will at least try to post some kind of rubbish at some point.

Anyway. Moved into Claycroft on Sunday, but I’m already starting to regret doing so really. It’s exceptionally quiet - on my corridor of eight, I’ve only met 2 other people so far. It’s somewhat depressing really, as it’s would be quite nice to be able to talk to somebody before going completely insane from lack of contact. I’m going to give it a couple of weeks, but if things continue the way they are, then I might move out. I’m not sure yet. The major plan at the moment is to spend as much time as possible in the maths department so that I can avoid the complete silence of Claycroft.

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Continue reading “Not the best start to term”…

6:11 pm | Posted in Maths, University, Whining | 1 Comment » | Show comment » | Hide comment » |

Well, after a bit of fiddling, the AJAX search is now fully operational. I think it works pretty well - it’s certainly quite transparent and saves a lot of room. It hasn’t been fully tested yet please let me know if you run into bugs.
IE had some… interesting rendering issues that need fixing in relation to opacity. For some reason, if you don’t set a background colour then font rendering goes completely crazy and everything looks awful. The moral of this story: IE6 doesn’t like opacity unless everything has a background.

Other than that it has been a pretty busy day. I’ve been up and down to Coventry. Most of the time the journey is fine, but today the M6 decided that it was going to hate me. It took me two hours to travel about 25 miles - average speed, 12.5mph. Usually I can do it in half an hour.

The trip did serve a purpose, and hopefully in a few days time I should have a clearer direction of where the project I’m working on is going. However, for the time being I will simply leave you with a lovely formula to show off my LaTeX renderer, as I really must be going to bed.

11:20 pm | Posted in Maths, Site Development, Whining, XHTML/CSS | 5 Comments » | Show comments » | Hide comments » |

In all the excitement of setting the blog up, I completely failed to realise that I hadn’t posted this year’s exam results. I do it every year so that I have a track of what results I got, so if you really can’t bear to look (for whatever reasons) I suggest you turn away now.

I must warn you that this is a very long post, and probably not of interest to most people. Only read onwards if you’re really interested in maths, or possibly want to find out just how crazy I really am.

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Continue reading “Exam Results”…

8:58 pm | Posted in Academia, Exams, Maths | 5 Comments » | Show comments » | Hide comments » |

Well, after a long and arduous battle with exams, I’ve finally finished my third year. I don’t really want to comment on the exams – not that they went particularly badly, it’s just I’d rather wait until I get the results. So, instead, I will comment on the various things that I’ve been doing inbetween.

The first, and by far most exciting was my 21st birthday. This has been quite amazing, and my utter thanks to everyone that got me gifts or just said happy birthday – it’s something I’ll remember for quite some time. My main present was the brilliant Canon Digital Rebel XT, otherwise known as the EOS 350D.

Some explanation may be required. My dad in his early years was a professional photographer for Land Rover. He moved onto do video work, and similarly I share his passion for video and photography in general. I bought myself a happy–snapper Sony camera at the beginning of the first year, but up until this point was somewhat underwhelmed, since I wanted more control with how exactly I wanted the image to be taken.

So, I now have a Digital SLR camera, which is quite frankly an amazing piece of technology. For those that are interested in getting a DSLR camera, I really have to suggest the 350D. I found it a breeze to get into, and it’s extremely easy to use and get to grips with. The build, whilst a little plastic for my liking, is very solid. I highly suggest you get the lens kit – you get a 18–55mm EF–S lens which provides pretty good quality despite the plastic exterior. It’s not brilliant, but for a budding amateur like myself, it’s a good start.

Unfortunately the 18–55mm really doesn’t have enough reach for my liking. I went out earlier in the week with Mark to take some snaps of the nature reserve on campus, and while we were there I spotted a number of shots that really needed a telephoto lens. This is where things start to get tricky, because when you’re on a limited budget like me, lenses aren’t generally an option.

However, I decided it was worth investing in. I spent the majority of the day researching various lenses, reading the EOS FAQ (which is an excellent introductory FAQ for beginners) and eventually came to the conclusion that Canon didn’t make any decent enough lenses for the prices they offered. I really, really wanted the 75–300mm USM IS lens, but at £360 it was just far too much to pay. In the end, I decided to get the Sigma 70–300mm APO Macro DG. According to all of the reviews I’ve read, it’s a decent lens for a bargain price (£165) so eventually I decided to take the plunge. That should turn up on Tuesday.

So, for the time being, I won’t be buying anything else for the camera. I should have everything I need for the time being, although I would absolutely love a Canon L–series lens. However, that’s way off in the future as far as I’m concerned. Anyway, with all of this photography lark, I’d really like to get the website up and running so that I can host my images nicely. So there’s that to work on tomorrow, and then we’ll see what happens.

That’s far too much for tonight, I feel, so I’ll sign off for now. Toodle pip.

10:15 pm | Posted in Maths, Photography, Randomness, Warwick Blogs | 3 Comments » | Show comments » | Hide comments » |

…or not.

I am, of course, talking about that most delightful of subjects, Measure Theory. The examination in question was held this morning, and it is fairly safe to say that, barring moderation, I will be failing that course quite badly.

My major problem with the exam was the style in which it was set. Frankly, it was clear to me that he simply couldn’t be bothered coming up with some decent questions. Pretty much everything on the paper was a 10-mark question, and two questions were split into 5/20 mark parts each.

I did the majority of the first question fairly well, I think. But unfortunately that’s where the limit of my knowledge reached. The second question was basically a lovely “state and prove the Dominated Convergence theorem” – 20 marks. Right, okay. Maybe that’s a reasonable question. But to just say “prove it”, and not break it into any sort of parts or guide you in any way is just lazy and completely unacceptable. Especially when you give the ultimately useless advice of “don’t try to learn large proofs, learn the ideas!!” on your website.

The third question was split into 15/10 mark parts. Yet again – absolutely no guidance at all, so I basically had no clue whatsoever. Question 4 was another lovely 20/5 part. The 20 mark question? “Prove f is in L1(0,1)”. Great. Thanks so much. Not even so much as “using theorem x”, or “Hint: try this…”. Just prove it. Finally, another lovely question on Lp spaces, and another lovely 15/10 mark split. Just amazing.

I don’t usually go off on people and examinations like this, because I do believe that if I do badly in an exam, 99 times out of 100 it’s going to be because I didn’t bother revising something. But giving advice on the website and then setting the exam on stuff that you told us not to revise fully is just a complete waste of my time. I spent a lot of hours sitting and finishing off the assignment questions, and to what end? I could have just sat there twiddling my fingers and I would’ve come out of that exam feeling exactly the same.

I left after about an hour. Quite a few people left after me, and maybe the fact that so many left in an exam that’s supposed to last three hours will give him a gentle hint. Some people came out saying that they didn’t think it was that bad, but to be honest, those guys are going to be very good at every exam they take or just got lucky. If you sit down and take the time to memorize the proof of the Dominated Convergence theorem, then that’s 20 marks, no sweat. If, like me, you didn’t think it was going to come up because everything pointed towards it not coming up then you’re in a lot more trouble.

Sure, I’m not the best student in the world. But I can do some of Measure Theory. The reason that I screwed this up so badly is that unless you knew how to do all of Measure Theory or were lucky enough to know the right bits, then the exam was a disaster.

So, what advice would I give coming out of this exam? (Not that anybody will listen, but hey).

To Dr. Valeriy Slastikov: This exam was unfair, period. I’m not unintelligent, but as a result, the hard work and effort that I put into revision counted towards precisely nothing. That is the most utterly frustrating feeling that one can get out of mathematics. Please take five more minutes to put together questions that aren’t completely impossible for those people who aren’t absolutely brilliant.

To second year students: Don’t take Measure Theory unless the lecture course is altered or the lecturer is changed. Simple as that.

PS: Please don’t bother writing comments if you’re going to say “hah, you deserved it you idiot!!!!oneoneone” because I can’t be bothered dealing with that sort of nonsense. These are my opinions, and if you disagree that’s fine, but please be constructive.

2:14 pm | Posted in Exams, Maths, Warwick Blogs | 3 Comments » | Show comments » | Hide comments » |

Well, had the old double-whammy yesterday and overall it was a bit disappointing.

Started with Introduction to Topology in the morning. As soon as I turned over the paper and read the first question, I knew that something had been drastically changed. I’ve done the past five years’ worth of papers, and, apart from one year which was done with a different lecturer, the format of the paper hasn’t changed at all. Basically the format is topologies, compactness/connectedness, identification maps/quotient spaces, the fundamental group and finally surfaces.

This year, the overall format was the “same”, but the standard of question was much harder. It came as somewhat of a shock to the system, but I don’t think I’ve done that badly. Amazingly, read the proof of Lebesgue’s lemma, and it came up on the exam. Unfortunately I completely forgot the proof and couldn’t answer in there. Oh well. Somewhat annoying was the lack of any “give without proof examples of…” question which would have been extremely useful. Overall though, I’m hopeful of a mark in the 70–80% region.

Combinatorics was, unfortunately, somewhat of a different story. I (barely) answered 4 questions worth of material, and I think that overall I’ll be quite lucky to get around 50% of the marks, tops. Mostly because I made all of it up. Hopefully there’ll be a certain degree of moderation as I think everybody found the exam quite hard. The annoying thing was the presence of probability stuff in not one, but two of the questions which I found extremely annoying – after all, I have pretty much no knowledge of anything to do with statistics at all.

So we’ll see. One last exam on Monday before three more weeks of revision, and then the second lot starts. But before that, the joy of Measure Theory. That could be very interesting.

10:23 pm | Posted in Exams, Maths, Revision, Warwick Blogs | No Comments »

So the first exam, Topics in Mathematical Biology, is all out of the way and done. My impressions were that it was fairly similar to the last two years’ worth of past papers, and having done those and the question sheets, it made it slightly easier. However, I couldn’t help but feel that the questions themselves were quite bulky. I found there was an awful lot to do for each question – especially the first, which took me about 45 minutes!

I attempted questions 1–3 and 5. I only answered question 1 in its entirety due to immense time constraints, but I got the vast majority of the work done. For the most part it seemed fairly correct. Unfortuantely I couldn’t quite remember how the very end of the singular pertubation question was supposed to work, so even though I’d got down to the inner and outer solutions, I couldn’t match them up properly to get the composite which was annoying. However, I gave it a decent shot so we’ll see what happens.

Question 3 was actually quite interesting and I very much enjoyed it. I did manage to complete all of the parts barr the very last bit, for which I basically scrawled something down when we were told to put our pens down. Managed to get the same answers as the question, so that’s got to count for something.

Didn’t attempt question 4 since I know next to nothing about lambda-omega wavetrains, so sat down and did question 5. Didn’t do the initial 3-mark starter question as I meant to come back to it later but again, didn’t get around to it which was a bit annoying. Got through most of it with ease, but unfortunately discovered a mistake in the very last part which means that I’m going to have lost a couple of marks.

However, it’s all over and done with, and I’m fairly pleased with what I’ve written. I can’t account for moderation and stupid errors on my part, but I guess that 70% isn’t an outrageous estimate. I’d be very pleased with that, considering I only actually went to one of the lectures for the entire course.

Next exam is on Friday morning, and it’s Introduction to Topology. I’m actually really looking forward to that since it’s one of my favourite lecture courses of all time. Unfortunately I also have Combinatorics immediately afterwards, so tonight will be spent completing the very last topology paper, and tomorrow I’ll mostly do Combinatorics.

So, we’ll see how the both of those go. Will hopefully update the blog afterwards, but that depends on how much time it’s going to take since the dreaded Measure Theory is on Monday morning. Eek.

8:31 pm | Posted in Exams, Linux, Maths, Warwick Blogs | No Comments »

Well my brain is thoroughly fried; just completed the 2002–2003 past exam papers for Combinatorics and Topology, and now I can barely concentrate so I’m going to take a large break and try not to think about how much I’m going to screw up Measure Theory. Anyway, thought I’d post another entry and see if I can get myself on a roll. Like that’s going to happen.

So, last night I mainly concentrated on getting this homemade YUV overlay built, and it seems to have worked nicely. The problem wasn’t Mesa, more the fact that I was generating 5 textures/frame, and telling OpenGL to overlay them in a very inefficient way. After spending some time reading up on Cg shaders, I created a basic fragment shader that did the job super quickly with only three textures. So I’m happy.

The other topic on my programming agenda is the blog. I really want to get going on my own website, and the blog is quite an integral part of that. I’m quite picky when it comes to having multiple copies of things, and I don’t like the idea of all of my original blog entries being separate from the blog entries here. So I’m going to have to come up with some way of keeping a central store of blog entries and comments, somehow. I was thinking that I might use a cronjob’d php script to grab entries and comments via RSS or similar, then update the database accordingly. But again, there are problems to this approach – what happens when I get a load of entires on here?

Bah, I’ll have to thnk of something. But besides that, I’ve been playing around with PHP’s PDO objects and they’re very cool. I’ll never have to worry about manually escaping my SQL data again. I’ve created a basic abstraction layer for some common functions, but I’m sitting here wondering whether it’s really worth it. Right now, I’m thinking “probably not”.

So those are the things going on at the moment. I should probably be revising, but I’m sick to death of it by this stage in time. Can’t wait until next year – the more 100% assessed modules, the better.

4:59 pm | Posted in Computing, Maths, Revision, Warwick Blogs | 2 Comments » | Show comments » | Hide comments » |

Well, it’s been a whole load of time since I posted, mainly due to revision and lazyness on my part. So I thought I’d post a quick update on what I’m doing – not that anyone will be all too interested.

So I’m back in Walsall after spending a week down at Sarah’s. Unfortunately, things haven’t been brilliant on the revision front. Whilst I’m mildly optimistic about Combinatorics, Introduction to Topology and to a lesser extent Topics in Mathematical Biology, I know that Measure Theory is going to be awful. I’ve not done a lot of work for it, and to be honest, I just don’t understand a lot of the material.

However, on the upside, I’ve finished all of my Topology and Topics exercise sheets, which is something that has never been done before. I’m now at the stage where, a week before the dreaded exams, I’m getting my act together and doing three past exam papers a day. So maybe there’s hope yet; we shall see, I suppose. I figure that even if Measure Theory goes badly, I can still pull it up with some better marks from the other modules.

However, I didn’t really want to talk about exams so I’ll talk about something equally as boring – programming. Been playing around quite a bit with two things over the holidays. Firstly – and this has been on the agenda for some time now – coding an OpenGL GStreamer application to map video onto a cube or some other random object. Surprisingly, this was initially very easy, once I’d found out how to actually get the contents of the GStreamer buffer into my program.

Basically I use decodebin to get the video playback working, and then pipe it through ffmpegcolorspace to get a nice RGB texture. Then, I use fakesink and a handoff function to actually generate the texture to screen and map it onto a cube. The hardest bit was actually finding out about the handoff function – it’s buried deep inside the GStreamer Plugin Guide, which is quite annoying. However, it does look quite cool. You can even take a look at it for yourself if you’d like.

Even so, I wasn’t quite satisfied. The biggest speed hump is the ffmpegcolorspace conversion, as generically most video files use some kind of YUV format to store video frames. Typically, and somewhat ashamingly, there’s no general way of dealing with YUV textures in OpenGL – all of the extensions out there generally suck, and don’t work for different versions. Plus, none of them cope with 4:2:0 planar YUV, only 4:2:2 pixel-packed for the most part. So some form of conversion to RGB is required, and a significant amount of CPU overhead is incurred in the process.

For the last couple of weeks I’ve been looking at various ways of efficiently using the GPU to do this conversion for me. Colour matrices were the first option I looked at. Basically, given some texture, one can use a colour matrix to remap colours in any given format. However, the major problem is going from 4:2:0 planar to 4:4:4 pixel packed, and that itself incurs quite a significant overhead.

Blending textures is possibly the best way of doing this. Basically, one generates 5 different textures along with using a simple colour-lookup table. Firstly, we lay down the Y channel as a luminance channel. Then the additive U, then subtractive U, and the same for V. In effect, just layering one channel on top of another to simulate the YUV->RGB conversion in the GPU.

However, there are again problems with this. The naive approach is to redraw texture upon texture, which means that every pixel needs to be redrawn 5 times every frame – at 25fps, that’s 125 times/second! In order to get the most out of the GPU, I used the ARB_multitexture extension, which allows you to layer textures extremely quickly in one pass. I also delved into the world of shaders to try and work out whether it might even be worth usnig only 3 textures and doing the RGB conversion through a simple ARB fragment program. This is something I’m still looking into.

Unfortunately, although this actually works and I’ve tested it, it’s still very very slow. However, I’m using quite a crap Intel 915GM based GPU under Linux. The i915 driver is not particularly good at the moment, and upgrading to Mesa 6.5 seems to have made matters even worse. glxgears is showing only 600fps – I should be getting at least 1300 according to other guys with the same card. So I’m guessing – and hoping – that the problem lies with the drivers and not my card. When I get back, I’m going to check it out on my Radeon 9800 and we’ll see how that copes.

Anyway, that’s probably enough for now. I’m going to reboot and see if I can get this all working nicely.

10:00 pm | Posted in GStreamer, Linux, Maths, Revision, Warwick Blogs | 3 Comments » | Show comments » | Hide comments » |