the singularity of being and nothingness
Archive for September, 2014
The Stable Marriage Problem
Sep 8th
While I was on the road this last week, I watched a video on one my favorite YouTube channels: Numberphile. This video discusses the Gale/Shapley algorithm for solving the Stable Marriage Problem.
If you’re unfamiliar with the Stable Marriage Problem, consider this:
You are the ruler of an island kingdom on which you have an even number of males and females, all of whom are of marriageable age. What you want to do as ruler is to create a series of perfectly “stable” marriages which will provide a good cement for the durability of your society.
In this scenario, a stable marriage is defined fairly simply as a union in which the man does not prefer another woman over the one to which he is married, while the other women also does not prefer the man over the one to which she is married.
For simplicity’s sake, consider two marriages:
- Ron & Stacy
- Doug & Marian
Let’s say that Ron prefers Marian over Stacy, even though he’s married to Stacy. If Marian prefers Doug to Ron, she has no reason to leave Doug for Ron, and so her marriage is considered “stable”. Likewise, since Marian has no reason to leave Doug for Ron, Ron also has no legitimate More >
Ext JS 5: View Controllers
Sep 1st
If you’ve been paying attention to anything Sencha has been talking about since the release of Ext JS 5, you’ve certainly noticed a shift in emphasis in application structure. With Ext JS 4, Sencha provided a pretty robust architecture for developing scalable applications in an MVC(ish) approach. This was a MASSIVE upgrade from the 2.x and 3.x days in which the kind of plumbing needed to pull off something like this was cumbersome to build and, of course, not native to the framework itself. Despite its shortcomings, 4.x’s MVC provided the tools to build applications on a solid foundation very quickly and in a manner that was scalable and reproducible.
But of course, scale always reveals the shortcomings in architecture. As great as Ext JS 4.x’s MVC is (I still like it…), sufficient scale coupled with lack of foresight on the part of application developers can lead to collisions in events and selectors. Additionally, without facilities for easily creating and destroying controllers, scaling a 4.x app always means a directly proportional increase in resources required to manage an application’s controllers, which (under normal circumstances) exist perpetually from the moment the application is initialized.
Partly in response to these challenges, and partly as a natural evolution of the More >
