Thursday, 26 November 2020

A proper Zoom backdrop, finally

 We have been having some work done at home, to have our loft changed into a bedroom and an office for home working.  We have had a bookshelf built in to one of the rooms, and it has just been populated by books, so finally I can take a photo and have proper background to my Zoom calls, which I understand is supposed to be a full bookcase

Wednesday, 4 November 2020

Online teaching & Maple Calculator

 It's the middle of the semester, and it's my busiest semester, in which I teach two full 15-credit final year modules – i.e. I am teaching half of a student's full time effort, and with the extra preparation of online lectures, online tutorials, videos of answers to problems, more time on online discussion, as well as all the non-teaching parts of my job, I am finding myself working after the family has gone to bed most days.  Not a position I ever try to get myself in, but I'm more or less resigned to it for the rest of semester.

For most of my lectures and problem solution walk-throughs I'm using a video of me writing on a tablet device, accompanied by my voice.  It works tolerably well, though not without glitches. I'm getting increasing adept at re-opening the whiteboard app when part of my writing hand accidently touches a part of the screen and closes it.  At the same time, my usage of mild swear words has never been higher, and no doubt the students will also be saying crivvens whenever they need to express some slight horror.

Some of the problem solutions I've been working through involve sticking in actual real-life numbers into calcualtions.  These are calculations a bit too complicated to do mentally, and I rarely find myself in need of doing such calcualtions so that I don't have an old-fashioned calculator to hand.  I have, of course, a computer, and also a smart phone, and usually I end up using the calcualtor function on my smart phone.  As I wrote an equation on my tablet a couple of weeks ago, I did find myself musing that it would be nice if there were an app to recognise the equation and do the sums for you.  Lo and behold, of course there is. One of the courses I am teaching right now involves the use of the programming language Maple and there is a app written by the Maple people called Maple Calculator.  It has exactly this function; you can take a picture of some mathematics with a camera, it will recognise it (hopefully) and then evaluate it for you.

Here is an example of it working out a calculation for a kinematics problem in special relativity:

I tried to make sure that I wrote the equation very neatly, and indeed it seemed to recognise it okay.  The answer, though, is not what I was expecting.  The actual answer is around 1.73.  It took me a little while to understand why...