2009 April

• Maintaining State with YUI Event

  When one start writting Javascript in patterns like the module pattern, then sooner or later he would want to maintain the state when an event handler is called. The reason I am still using YUI to handle my event handling code is because I like how state can be maintained.

  (more…)

• Random Javascript Notes

  I am starting to like programming in Javascript, especially after understanding more about how Javascript handles scopes. Surprisingly this take me like a year to figure out how scope is managed. The result of the findings is that I start doing a lot of experiments and discovered more interesting stuff through them.

  (more…)

Random Posts

• Mixing Non-array and Array in array_map()

  array_map function is a function that I use the most in my php scripts recently. However, there are times where I want to pass some non-array into it, therefore often times I have code like the snippet shown below:

  $result = array_map(
'some_callback',
array_fill(0, count($some_array), 'some_string'),
array_fill(0, count($some_array), 'some_other_string'),
$some_array
)

  It doesn’t look good IMO, as it makes the code looks complicated. Hence, after seeing how the code may vary in all different scenarios, I created some functions to clean up the array_map call as seen above. Code snippet after the jump

  (more…)

• Resource Definition Framework

  As the name implies, Resource Definition Framework, or RDF in short, is a language to represent information about resources in world wide web. Information that can be represented is mostly metadata like title (assuming the resource is a web-page), author, last modified date etc. Besides representing resource that is network-accessible, it can be used to represent things that cannot be accessed through the network, as long as it can be identified using a URI.

  (more…)

• #nand2tetris is fun

  The Nand2Tetris part I at coursera is very much my first completed course. It was so fun to actually work through the material and it feels amazing to know how simple it is to actually build a computer from scratch. While it is simple, it doesn’t mean the course itself is easy though. I was struggling to get the CPU wired up properly that I spent two to three days just to get it working.

  (more…)

• Further Hack on the Multi-Dimensional Approximate Neighbour Search

  Traversing a tree structure often involves writing a recursive function. However, Python isn’t the best language for this purpose. Therefore I started flattening the tree into a key-value dictonary structure. Logically it is still a tree, but it is physically stored as a dictionary. Therefore it is now easier to write a simple loop to traverse it.

  (more…)

• Development virtual machines on OS X using VirtualBox and Ubuntu

  I have been following this excellent guide written by Benjamin Thomas to set up my virtual machine for development purpose. However, when I am starting to configure a Ubuntu Quantal alpha machine, parts of the guide became inapplicable. Hence, this post is written as a small revision to the previously mentioned guide.

  (more…)