Saturday, December 22, 2012

Bonjour for managing printers

If you choose "Include Bonjour" in Safari's Preferences like this:
 You get this:

Which is a massive time-saver. You can also tell at a glance if a printer is facing networking issues since it won't appear if it's offline.

Friday, June 24, 2011

Vertical spreads

A common options strategy is a vertical spread. A bullish call spread is called a debit spread because funds are deducted from the account, while a bullish put spread is called a credit spread. Examples for AAPL July 11 options strategies:

Sentiment: Bullish-Neutral
Strategy: Credit spread
Long 300 Put, Short 310 Put
Breakeven: $309.24
Max profit: $76
Max loss: $924

Sentiment: Bullish-Neutral
Strategy: Debit spread
Long 300 Call, Short 310 Call
Breakeven: $309.35
Max profit: $65
Max loss: $935

Note that the strike prices are the same, regardless if they're call or put options. Personally I prefer credit spreads because if the strategy is successful, the options expire worthless so I don't incur commission fees. This is not a trade recommendation and is only an explanation of some basic trading strategies.

Thursday, December 30, 2010

TRON: Legacy

TRON: Legacy was one of the more interesting movies of 2010. The following are some themes which were explored and contains spoilers, so be warned.

References to the Christian religion
Kevin makes CLU in his image, just as God made Man in His image. Man rebels against God, just as CLU rebels against Kevin. Man was supposed to be perfection, just as CLU was supposed to be perfect in his world. In the Bible, Man tried to reach the heavens by creating the Tower of Babel; CLU tries to reach the outside world through the portal which is a beam of light shining skywards. The Light Transporter with its captured programs on board, serves as a metaphor for Noah's Ark.

References to Eastern philosophy, Taoism (duality), Sun Tzu's Art of War
Kevin does not engage in open warfare with CLU. When CLU tries to exert his "will" on the world, he upsets the cosmic harmony which runs counter to Taoist philosophy. When Kevin and CLU merge, the world ends because they are a natural duality i.e. Yin-Yang, passive (Kevin) vs aggressive (CLU), matter and anti-matter, male and female, so on and so forth. Thus it is meaningless to think of Kevin or CLU as independent forces of good or evil, for they are inter-dependent.

Biology & Evolution
Isomorphs are life-forms discovered independently and were not Kevin's (God's) creations. The existence of isomorphs are possible because organisms governed by simple rules are able to exhibit complex, non-random features (cellular automaton). When Quorra gets wounded she is restored to health by manipulating her "code", which is analogous to DNA/gene therapy (the movie even uses a double helix, duh) which repairs "damage" to the genes. Programs placed in the games are expected to "evolve" (self-modifying), with the best ones facing off against the champion Rinzzler.

CLU's singular mission is to achieve perfection by ridding the world of imperfect beings. Most cultures place undue emphasis on youthfulness as perfection, which is why CLU appears as a human male in his prime. Even Quorra (played by Olivia Wilde with her nigh-perfect symmetrical features), except for her quirky hair-style and mysterious "tattoo" on her arm which marks her as an isomorph.

Wednesday, December 22, 2010

MINI Habitat Singapore does not perform Preventive Maintenance

Both the driver and passenger sun visor hinges on Eve's R56 MINI were worn and were close to breaking. The passenger-side was replaced under warranty while we were told that that we had to wait for the driver-side to be stocked, which would be outside the warranty period.

When we sent it back for servicing (for a leak from the oil filter), we were told we had to pay for the visor despite being assured that it would've been replaced at no cost to us.

Additionally, they told us that the engine mounts were worn and had to be replaced at about $1000, despite having no prior indication that they were due for replacement.

Download the audio where the service manager states clearly that MINI Habitat does not perform preventive maintenance.

If that does not sound ludicrous to you, then consider the implied message. e.g. if your MINI develops a crack on the windscreen, and as long as you can see through the windscreen and the elements do not hinder your driving, MINI Habitat will not replace it. Or maybe one of the brake rotors develops a severe crack from normal day-to-day driving and they do not replace it because technically it can still perform its function. Until it suffers a catastrophic failure and breaks, sending your car spinning into the armco.

Of course I understand parts exhibit accelerated wear-and-tear from atypical activities like racing, abuse or just plain high mileage. But Eve's car is driven daily on Singapore roads for work purposes. It's not like she's out to win the 24 Hour Le Mans. The other point that I'm unhappy about is that the wear on the engine mounts were undetected since the last servicing, which was about a month prior. Either it wasn't checked then or the wear significantly worsened since that time. Which is the more likely explanation?

My family has 3 Saabs which is also under Trans Eurokar but we've never had any problems with the workshop servicing. So let me make this clear: I'm not bashing Trans Eurokar.

As a customer, I have no complaints about the MINI. In fact I feel the car drives very well and is comfortable enough for long-distance touring. However the after-sales is worse than amateurish. At least with amateurs you're dealing with people who are trying their sincere best to solve your problems.

I will not recommend this car unless you have access to trustworthy professionals who specialize in it.

Thursday, November 11, 2010

Land of Lisp book review

Land of Lisp is an intermediate-level book that teaches Lisp by way of game programming. Interspersed with light-hearted illustrations, LoL is a real page-turner and is one of the most interesting programming books I've read. Important Lisp concepts such as macros, higher order functions and generic programming are clearly explained. One whole chapter is devoted to Lisp being applied to Domain Specific Languages, which is highly applicable and relevant to modern web programming. Along the way, the author also teaches fundamental concepts such as recursion (although not as much emphasis on this as compared to Scheme, for example), code reuse (the "Don't Repeat Yourself" principle), functional programming, closures, basic algorithms like MiniMax, depth-first search and a whole lot more.

Because the author assumes the reader has a basic grasp of his operating environment, setting up a Common Lisp implementation (editor/compiler) is not covered in detail. If that idea is too daunting for you, then you may wish to refer to the beginning chapters of Peter Seibel's Practical Common Lisp or David Lamkin's Successful Lisp as a starting point and come back to LoL when you're more comfortable with how things work.

All in all, I would say, "buy this book!". Highly recommended.