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Archive for November, 2011

1, 16, and Big 30

On December 17th I will turn 30 and I recently went through some old photo albums trying to gather some memories from favoured times in the past — times when life when generally quite easy and fun. This made possible and easy to assemble the following collage which spans mostly a year or more after birth, 15 years after that, and another ~15 years later, at age 29 and 11 months.

Roy Schestowitz in 1983

Roy Schestowitz in 1983

Roy Schestowitz in 1983

Roy Schestowitz in 1983
1983 (with my dad)

Roy Schestowitz in 1984
1983 or 1984

Roy Schestowitz in 1991

Roy Schestowitz in 1998
1998 (age 16)

Roy Schestowitz in 1998, Miami

Roy Schestowitz in 1998, Orlando

Roy Schestowitz in 1999

Roy Schestowitz in 2011
2011 (days ago)

Roy Schestowitz in 2011

Roy Schestowitz in 2011

Making Spirals in Octave/MATLAB

Occasionally, in numerical programming, one may wish to plot or instantiate a grid of a circular (or spiral) nature. Here are some code samples for those trying to achieve it. The following sets some values of interest:


Now, let us generate some linear, equally-spaced points:

t_map = linspace(0,lines*pi*2,lines*degrees*2);

What we have here is the 2 for 360 degrees, which may depend on what one tries to achieve. For the more complex case shown later, this will be essential. Now, let’s do the sine/cosine magic:

x_map = t_map.*cos(t_map);
y_map = t_map.*sin(t_map);

This can be plotted with plot(x_map, y_map), but let’s do something more interesting by assigning colour to the sample points and then plotting them as dense dots. The following would work:

  for ll=(size(x_map,2)/2):-1:1

The values here are rather arbitrary and can be used for demonstrative purposes. The problem itself seems to be commonly recurring, thus the need for a blog post. Different colours can be assigned to sample points, which achieves something like the following:

Spiral examples

Back to Rowing

TODAY I began preparing for a rowing competition like those which I have not paricupated in for years. This one will be a sprint equivalent which relies on sheer strength and proper technique (the latter requires more practice) and I believe that with enough preparation I can beat the British record. My diet and my exercise (not to mention sleep patterns) will be changed accordingly in the coming month and I look forward to bringing another trophy home before I turn 30.

Why This Blog is Hardly Active Anymore

Roy Schestowitz

I RARELY find the time or even the need to write about my research in this blog, either the Linux- and software-related research or my job where I study geometric methods and develop new techniques that nobody tried before. The reason for inaction regarding the latter is that I cumulatively prepare a large report (over 300 pages so far) which will be published in full in this Web site when it’s all polished, along with code. I posted some material before. For the former, there is a site dedicated to that and it is called Techrights. That site took many years to build a reputation and PageRank 7. It now attracts a huge number of visitors and serves as my main blogging platform (I have about 10 installed WordPress blogs in total). became a dumping ground for random thoughts and stories that do not fit elsewhere. Thanks to all those who follow this blog in spite of disorder.

For more regular updates from me, please also follow Techrights. It is more polished than this Web site.

Expression With Keyboards, Voice, and Physical/Frontal Interaction

The difference presence and sound can make.


Keyboards are a wonderful input device because they are accurate and they use the fingers, which we can use in unison in very clever ways. It’s nature’s gift to our species. But not all keyboards are created equal. One might have to look at the keys to map the letters in one’s mind, e.g. in case the keyboard is a numpad on a phone. These are designed to minimise space, but always at the expense of productivity. Some mobile form factors like tablets have the same problem. It’s a limitation. The change in keyboard technology has led to a shift in communication, mostly abbreviation; the very short messages are simply the result of limitation, not young people’s preference for illegible sentences. This is why I use a PDA with foldable keyboard, I am using it even to write this very post. But I generally get flak sometimes for being honest about the lack of appeal for SMS — taking like 10 times longer to express oneself there than verbally. With keyboard I am always on par with speech, bar the need to proofread (this is why audiocasts, for instance, have some clear advantages). I like typing and I type fast, but nothing ever beats speech and there are no typographical errors in speech. It also allows one to think clearly by not getting slowed down by the fingers (that in most cases cannot catch up with the speed of mind or the voice in one’s head). In order to communicate with people rather honestly, the time limitation is sometimes required. Without practice, there is less time to spin; some prefer to judge by using more facial expression as well, but that is another discussion altogether (direct, real-life interaction). Just because people cannot hear another person’s voice or tone of voice means that they are missing a lot of the message, assuming one is serious or whatever even when sarcasm is used. When face muscles can be observed, then untrained liars can be called out too. The bottom line is, depending on the medium used for communication there can be vast differences one needs to be aware of.

As one can probably imagine, without people hearing each other, let alone having visual communication, people are simply using just a small portion of human interaction*. There are some numbers, percent-wise, from about 15 years ago and less. They try to quantify the extent to which each element of communication counts. These talk about how much body language and voice amount to when it comes to signals we humans interpret to detect love, fear, anger, etc. Like staring at someone. It’s animal instinct to find that unnerving — something about feeling like prey. Try that with a dog or a cat and see what they do. That would be a good example of communication without words or even any facial muscles, just eyesight directed without motion at an animal. Truly a good case study in interaction with very low entropy, eh? The longer it does not change, the less comfortable the person/animal will get. It is something in he reptilian (older inherited) parts of our brains

An animal that cannot detect being watched will be left behind in the pact and caught by lions or whatever. But those who are too careful are also not too well off. By extension, this generalises to other things. For instance, a girl too afraid of guys might not meet some people or miss an opportunity, whereas one who over-trusts people might become a victim. So striking the balance is an evolutionary process wherein one adapts one’s compass to know what’s a threat and what’s not. Messages in general are ambiguous and the less communication elements are available, the greater the number of possible interpretations. One cannot tell for sure how it’s viewed in the context of non-vocal communication, unless some expressions of emotion (like emoticons) get used spuriously to compensate somewhat.

If the screen has no smiley signs, then it might, in one’s mind, evoke the feeling that that the other side is angry, upset,apathetic, or simply overly serious. Just 3 symbolic characters can make a lot of difference by clarifying intent or feelings. To substitute something like an image on the screen we still depend on visual cues. They appears as mere characters, but to the observer at the other side they are not. But overusing them would make a computer geek look a little awkward. Formality is another thing and the frequency of typos under different circumstances is also a missing variable. In certain places one might proofread, whereas in others one might just be typing as the mind goes along, and even reading while one goes along typing. It feels a little write-only otherwise, almost akin to those typists who sit next to the judge in a high-profile case, where basically rather than listen and type someone else’s utterance one might try to express what goes through another’s mind, letter by letter. If I don’t have to ghostread and proofread, then it’s a joy as that basically means one can write sort of like one speaks, maybe more formally, maybe less. This post too won’t be reread as it is intended to show what happens when one types down some thoughts without planning in advance.

* We evolved to use full interaction, not telegraphs or remote audio such as telephones.

European Union/Commission Saves Us From Big Brother


According to the news today (the theme one comes across by listening to any radio station in the UK), continental Europe comes to the rescue again. Here in Manchester, getting a cancer-causing scan is mandatory for boarding any plane in Manchester Airport. This is very profitable for some companies and their cronies who devised these ludicrous measured due to one guy with explosives in his underwear (an old incident whose casualties count is 0). As I have been stressing for almost a year, those machines that scan people as though they were suitcases are assured to kill (in the long run) more people than they would save by preventing explosives from going on planes through one’s breast area, crotch, etc. The whole thing is a sham and a cancer-generating pipeline that makes some industrialists rich. So anyway, the news here is that removal of all such machines has just been demanded by the authorities in the EU (probably Belgium and the surrounding aristocracy). This is good. No more will I need to confront airport staff over their stubbornness; why should they impose X-ray scans as a sort of blackmail prior to travel? What have we as a civilisation sunk to? And that’s not even delving into other issues such as the acquisition (with alleged retention) of naked pictures of every citizen who travels on a plane (via an increasing number of airports). Civil liberties — not just our health — are being jeopardised without taking simple risk calculations into account. Several months ago I did some maths related to this and came to the conclusion that unless those scanners can prevent 200 large planes from going down by detecting a passenger with explosives that cannot be detected in other means, the deaths due to the cancer will be greater. In order words, by placing those machines in the airport (lethal X-ray rebranded) they sign the death knell/sentence of many people and hardly save any lives. On numerous occasions I had discussions about this with staff who works around those machines and never could they provide a compelling explanation for why they participate in it (big brother cooperation). Perhaps the “I’ve got a mortgage to pay” is the best they can do. One persuasive method is to clarify to these people that their health too is at great risk and information about it withheld. Hopefully those machines will all get canned just lime the ID cards. Liberty and security don’t sit well together.

Is Shutting Doors Always Necessarily Safer?

SOME DEBATES are rarely tolerated because they challenge fundamental assumptions that are repeated over and over again. One of them is that by locking doors at all times we are all very much safer, insular from a world we assume to be only hostile and never altruistic. And this assumption will be challenged now with an example.

When I go to bed I generally always keep my door open — both main door and bedroom door of the apartment. Why? Well, because I know all my neighbours in the area and I generally trust them. Some people think it’s over-trusting, but they just don’t know the neighbours. They are people whom I know. I also don’t think of them as physical threat to me, in fact if someone was to assault them, I’d hurry up to help them, not having to struggle with barricaded doors. Statistically, break-in is not a high profile problem. It hardly happens and we have 3-layer gating, so one could intrude — maybe, at most — the ground floor. One might wish to worry more about heart attacks people might have than a burglar. And if a neighbour had a collapse and screamed for help, then a locked door would probably lead to a death that could be prevented.

I am generally in a position where I also realise that people like in Holland (famously even if it’s no longer true) would be in less risk. It is valuable to remember that when one locks oneself from the outside, he or she also locks the outside from oneself. Many issues are potentially caused by this. Ask a person why he or she gives a key to a neighbour or a friend. Sometimes when there is an issue like fire it’s good when someone else can rush in to extinguish it. A lot of people tend not to think of it, But here’s a thought: if a person gives keys to many neighbours, he or she might be robbed, even accidentally through loss of keys by another person. But robbery is not death. Basically, the person might want to consider how often — on average — for a neighbour to come in can help save a life or a home. In Holland, some people allegedly leave their houses unlocked (even whilst away). Then it’s a little harder to justify, as personal safety is not at stake.

Risk calculations are worthwhile. Like assessing the impact of war on drugs. Some people are shy to ask what would happen if these got legalised. What would police pay more attention to? Who would be locked up except the addicts? And these are legitimate questions. Not delving into these issues means that our law gets motivated by dogma and not always by pure logic that adapts to the times. Depending on the situation, it might be safer to leave the door open, especially when one lives on his/her own and is indoors.

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Original styles created by Ian Main (all acknowledgements) • PHP scripts and styles later modified by Roy Schestowitz • Help yourself to a GPL'd copy
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