(~5 min read)
This is the basis of all professional administration; actively maximise all good things that should happen; actively minimise all bad things that should not happen; and seek all good grounded opinion as to what is good, what is bad and why they say so.
Earlier this month the latest modifications to Dyalog APL had their annual outing. As usuall, those of us who had lots of experience with this dialect loved it. Those of us who had only a passing aquaintance with Dyalog, I am one, felt like learners without a teacher.
I remebered the flaw APL has, berzerk notation. Learning new APL features is like learning a new writing system. If you like learning new notation, APL is your thing. However, you have to motivate yourself to learn a new language principle, such as, how operators remove the need for iterators in APL. Like me, you wil have logged off after the first half-hour of an afternoon-long presentation.
What they presented was, I think, how hierachies remove the need for parsers, regexps, and filling systems. Honestly though, I will have to ask at the next meeting.
If you like learning programming languages as much as I do then you will have heard of APL. If you heard about it when I did, your first encounter with it will have been in a libruary with a text book a note pad and a pen. These days, however, you need to find a web site that runs an online APL and prepare a kata or two to code on it.
In the 1980’s, my text book started me off gently with 2+3 and, eventually, got me to to conjecture what the ackerman hierachy was. I did not just learn how to programme in APL, but also what APL was for. In case you are wondering; APL is mathematical; APL is array oriented; APL is for people who like something difficult to study, that is not just a kata.
Incidentally, the meaning of “kata” in far eastern languges is not “exercise” or “puzzle” or “problem”; it is “curse”. The confusion arose from its use in martial arts. “Draw your sword!”, says the referee, the competitor does so, without hitting the referee. Then says the referee,”You are cursed! Your enemy is standing and you are sitting! Draw you sword again!”. The competitor sits on the floor, his sword is at a funny angle due to his clothes. He stands and attacks in one motion, without falling over. “Well done, you are a hero!”says the referee.
Now, back to programming.
Given most of the above; you will not want to start your adventures in APL by installing it on your own machine, or by just searching for “tryapl”. What you will need to do is have some kind of learning strategy first. It is this step that gives most people the impression of APL as a difficult, over complex, and somehow pointless language. This is because most people have a kill the monster attitude to learning, that if only they get past the kata they know everything in one big bang. This is not true, and its disproof is one of the reasons that I like APL so much. A reason I was in the libruary that hot summer in the 1980’s was that, my tutors at my FE college decided that they wanted me to keep learning programming after my ‘O’ levels ended. By various means, such as Socratic Dialogue and, reading my subject notes, they made sure that I had a learning programme. An important step, that most people skip nowadays. In less hysterical language, have clear goals in mind and a defined way of achieving them.
Now, grasshopper, what is 2+3 and what is 2÷3 ? If you study it in the right order, APL does not much more complicated than this. You can write a DBMS in less than 20 statements. ditto a caching data shaper. ditto lots of things that I never seem to have time to do!
reading time about 10 minutes
Scenario:- I am chained to the sink, cleaning a frying pan clogged with pancake residue, using a scraper, soap, and water. I get to the point in this misery when I have half of the pan clean. I decied to now clean half of the dirty half. Then I clean half of the dirty bit I have not cleaned, and so on. I will only be released from this domestic misery when my frying pan is clean. If I take the unmodified systematic approach above, will I ever be free?
According to one opinion; a half, then a half of a half, then a half of that, and so on….. leads to an infinite series that never converges, so that you never have zero of the pan to clean and stay in the kitchen forever.
However, this can be exploded by pointing out that the problem is not about any old series but about sectors of a circle that can be formed by construction. These can also be formed by rotation, and sectors of more than one circle round can be formed by rotating the pan round more than once, so when the pan is clean on the right, I can turn it round, and clean the left. This however, leads to the systematic approach being modified, so it explodes itself.
Yet a third opinion, is that an infinite series that never converges can have a sum of any value, even infinite ones. So according to this school of thought, my systematic method will have me clean the pan almost instantly and leave the kitchen soon, even if there are many pans to clean, just like the unexploded second opinion.
I have been taking things easy this week. I have had two immunisations at the same time. I have been feeling a bit below par, therefore.
I am, slowly, in the process of writing a short paper about the behaviour of exponentials, for the British APL Association. I may post a summary here, after they have seen it.
This is a question that I am not asked frequently. However, at Bradlug’s Reboot Meeting this week, I was asked this by a new member. My reply, this time, was that Slackware has relatively plain looking installation and updating software, its mostly command-line stuff ,so that you are encouraged to use Slackware, rather than update it all the time. My questioner uses Ubuntu, where you install-use-remove software that you do not use frequently, and everything is done from the desktop or a browser. “Horses for courses”, I suppose.
(approx 5 min read)
Recently, I found the twisty turny way to a new Computer Club. One of its main interests is programming, I hope that another is programme design. On my first session I found out just how twisty turny a D programme can be. It starts with, enough import statements to take the space of an entire programme in APL to do the same thing. It does not use just for, but foreach, map and split as iterators. They tell me at the BAA that APL does not need iterators.
However, there is a usefull function in the D programme, an enhancement of startsWith. It does not simply match the head of a string to a single character but, to any of a string of them. It uses uniform function call syntax, and a default matching string, to simplify the interface to functionality. I suppose that it is this kind of insight into one’s own code that computer clubs are about, and the twisty turny rubbish that I coded in the mean time is just a run up to the heights of origional code.
(about a 5 minute read)
I have deep veins, so you can probably guess what this is about. Why am I having a blood sample taken? Or rather, why were some nice ladies trying to take blood sample from me, and failing?
If you guessed “Scientific Enquiry” you are right. The reseachers at SHEEER are giving me a DNA profile. Strictly speaking, they are trying to do so. However, despite puffy cussions, mineral water and biscuits, they were unable to get a sample this time. Now, I do not just have deep veins, I have sore ones!
(reading time 5 minutes)
If you are jewish, or even if you study the psalms in translation, you are probably familliar with a verse that goes something like this “And they shall form a single band to do Your Will with a whole heart” They being the people of the world, and the will being talked about being God‘s will. Those of a more mystic bent will probably know the 13 attributes of God, one being Slowness to Anger.
In the origional it is possible to mis-pronounce “a single band” and (especially if you are singing or praying in chorus) say “fellowship of the number one”. Not that bad, but in our second example you can go from saying “slow to anger” to “land of noses”. These both involuve one letter in an entire sentence. So what has this got to do with the price of Bacon ?It is a cause close to the hearts of many, dyslexia. They are the sort of well-meaning blooper that, when pointed out, can alienate a dyslexic from their own culture for a very long time.
reading time about 5 minutes
If I worked systematicaly, not just motivated by a spirit of scientific enquirey from time to time. I would be eating my own home-made low-fat pancakes for breakfast everyday, not just when I wake up on time and have eggs to cook with.
Not a happy happenstance you my think, but in my opinion, there is a certian olde-worlde charm to a spirit of scientific enquirey that more modern and conventional psycho-technology lacks. For one thing it is not always a defective, so it does not preclude me from being rational and cautious when I encounter something new. It is not always a rechercheral, so I do not always get tramiled into convention when I am in an experiment. This often leads to that rare phenomenon that the other reseachers are looking for.
What has motivated me to write this ? I am in the process of joining a medical research organisation, sponsered by a local university. I am trying to work out how to approach my first experiment with them and why they are keen on me joining them. I am not totally “the new boy”; I have been in medical experiments before. I think I will be more of “the man from outer-place”. I hope that I will not be dumped in the deep end first. It is also a long time since I wrote a letter to myself and this page is my way of getting back into writing.
It is, as I write this, less than half an hour to midnight. Therefore, pancakes for breakfast ? probably not. But pancakes for lunch and a surpise for modern science? I hope so.
poor-darrens-almanack 