November 2009
1 post
Clojure + Mathematica
A few people asked how I wrote a webapp using Clojure with Mathematica. The solution is actually quiet simple - Clojure runs on JVM and Java interop (ability to call any Java libraries) works great. Mathematica provides a J/Link Toolkit that allows you to control the Math kernel from Java.
Why Clojure?
You could also use Java and link to Mathematica, but Clojure has the advantages of a...
May 2009
1 post
Twitter Analytics using Mathematica
Twitter has been just about everywhere lately. As its popularity continues to grow, how do you keep track of the expanding list of friends and followers? As more companies are using Twitter to promote their products, good tools are necessary to manage hundreds or thousands of contacts and analyze their Twitter social graph . Twitter has an open api, and Mathematica is the best analytical tool...
April 2009
2 posts
Pair Trading using Mathematica
Pair Trading is one of the ideas that I have been very interested in, but could not find right tool for analysis. Sure, most traders use Excel, but that’s simply too many copying and pasting cells. Patrick showed me the cool things he could do with Mathematica, and I thought that might be the perfect tool for stock analysis.
So what is Pair Trading? In short, it is a market-neutral...
January 2009
1 post
Two reasons why most entrepreneurs fail
“by doing nothing, and by doing the wrong things.” - pg via Hacker News
December 2008
1 post
November 2008
1 post
October 2008
4 posts
“that code should be seen not as a static thing, like the answer to a math...”
– Paul Graham, on the one thing every software engineer should know
Ack bundle in TextMate - Faster Find in Project
One thing that bothered me with TextMate was the Find in Project function. In searching for replacement, Olivier pointed me to Ack!, which is an excellent tool to replace find+grep.
While doing so, I came across a nifty Ack bundle for Textmate. It’s REALLY FAST. Enjoy!.
September 2008
5 posts
Open source library for quantitative finance →
Open source framework for modeling, trading and risk management in finance. Includes Python binding. Despite the market turmoil, anyone wants to start a hedge fund?
(found via http://news.ycombinator.com/item?id=309198)
research done by mechanical turk →
brilliant! casual research by surveying random population using mechanical turk.
MemCache Flush All (for memcache_client )
Some times we might want to clear memcache without restarting memcache server.
When calling Cache.get / set, we are really using a wrapper module Cache that simplify access to memcache client.
To flush memcache, call CACHE.flush_all
Contact form for iTune support →
This link is hidden so deeply, it always takes me few minutes to dig it up again.
Ruby include, extend, require and load explained
The Ruby ‘include’ statement references to a named module; it appends features of a module into classes or other modules.
‘extend’ adds the features of a module to one instance (object) at run-time
‘require’ is used for loading nonmodule Ruby sources and binaries. ’require’ is similar to a ‘load’ ,but it will not load a file if it...
August 2008
3 posts
Git - revert / undo local modifications
To undo local modification to file
git checkout -f /path/to/file
To revert a recent commit
git reset HEAD~
Good reference for Git material: Kernel Hackers’ Guide to git
WatchTai Chi Demonstration by Master Yuan Zhen Wu, 32nd generation warrior monk from Shaolin Temple. http://shaolintemple.ca
approach on product design →
Paul Buchheit:
What is the humble approach to product design? Pay attention. Notice which things are working and which aren’t. Experiment and iterate. Question your assumptions. Remember that you are wrong about a lot of things. Watch for the signals. Lose your technical and design snobbery. Whatever works, works.
July 2008
9 posts
Restart Apache w/ mod_rails on Leopard
sudo apachectl restart
Hackers discuss about tradings →
two of my favorite subjects
“The only true wisdom is in knowing you know nothing”
– via Paul Buchheit
my current interests
programming languages, web frameworks, non-relational db, stock trading strategies, collective intelligence, minimalism
“Remember that time is money”
– Ben Franklin, 1748 (Advice to a young tradesman)
Blowing Up →
on Nassim Taleb by Malcom Gladwell - two of my current favorite storytellers
“he buys options on both sides, on the possibility of the market moving both up and down. And he doesn’t bet on minor fluctuations in the market. Why bother? If everyone else is vastly underestimating the possibility of rare events, then an option on G.M. at, say, forty dollars is going to be undervalued. So...
Questions to ask when launching new product
from http://evhead.com/2007/12/how-to-evaluate-new-product-idea.asp
* How difficult will it be to launch a worthwhile version 1.0? * Is it clear why people should use it? * How much value can you ultimately deliver? * How many people may ultimately use it? * How will people learn about your product? * How hard will it be to extract the money? * Do you really want it to exist in the world?
Hacker News Algorithm
(p - 1) / (t 2)^1.5
where p = points and t = age in hours
http://news.ycombinator.com/item?id=231209
“Steve Jobs’s ability to focus in on a few things that count, get people who get...”
– http://daringfireball.net/linked/2008/06/25/gates-itunes