Avin's Blog

Adventures in programming and data.

  • Financial Comparison of Air Conditioners

    I’ve been looking to get ducted AC installed at my residence and have had a few quotes come in. As the AC units, zoning and controls came with a similar set of features, I investigate the decision from an objective financial standpoint by ranking the offerings by comparing both the capital and operating costs. The…

  • Selecting by Option Value using Capybara

    Capybara’s select command allows searching a HTML select field and selecting an option that matches the supplied value by name, id or label text. Additionally, the match option allows the user to indicate the behaviour if more than one option is found. For example, match: :first will select the first item out of multiple matches,…

  • Auto-Mounting VirtualBox Shared Folders with a Linux Guest OS

    VirtualBox has a feature where a folder on the host machine can be shared with a guest VM. VirtualBox can also mount these shared folders automatically when the user logs into the guest OS. For Linux guests, these auto-mounted shared folders are mounted into the /media directory, along with the prefix sf_. For example, the…

  • History of Christianity

    Continuing the theme of history-based studies, the latest youth group study I led was on the History of Christianity. There is an incredible amount of literature available online, and we only covered a small fraction of events from Early Christianity and investigating the major groups of denominations. We also had a look at how Christianity…

  • Intro to Data Modelling

    When I was working for the Information and Data Management practice at SMS Management & Technology a few years back, I was asked to run a workshop for the Business Analysis Focus Group on data modelling. I put together an introductory presentation on data modelling targeted towards business analysts, which was a refresher on terminology…

  • Using Rails’ descendants in development

    Rails provides a nice method descendants that returns all subclasses for a specified class. However, config.cache_classes = false is a default setting in development.rb (for the ability to reload classes on the fly) and as this tells Rails not to load classes until they are referenced, then calling descendants will generally return an empty array…

  • Islam

    I decided to do a series of studies for our church youth group on various religions and started with Islam as Muslims form the second largest religious group globally. The intent was to cover the fundamentals of the Islamic faith, common terms that people may have come across, a brief history, and Islam’s relation to…

  • Malayalam TV

    Like most of the older folk in my ethnic community, my grandparents enjoy watching Malayalam television programming. They had jumped on the satellite bandwagon a few years ago and got good mileage out of it. However, at the end of 2011, Asianet, one of the primary channels they watch, moved from Insat 2E to Intelsat…

  • Coloured directory listings in PowerShell

    By default, PowerShell outputs drab directory listings. Unfortunately, there’s no built in solution to turning on colour, but it is possible with a few steps. This StackOverflow post gets us most of the way there. Towards the bottom of the question is some code that enables colourised output. I’ve modified it to suit my purposes…

  • Moving to a Windows JRuby on Rails development environment

    tl;dr I recently set up a JRuby on Rails development environment on Windows after using Mac OS X and Ubuntu VMs. It’s noticeably faster for development and more comfortable. I’ll stick with it. When I was first starting JRuby on Rails development, I started with a Mac OS X environment running from VirtualBox. I chose…