2021 January

• Statistical Analysis for Social Audit Project

  This is the formal draft of my statistical analysis report for the social audit project previously mentioned here. As the project is public by nature, I am cross-posting here for own reference.

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Random Posts

• Approximate Neighbour Search in Multiple Dimensions

  In the previous post, I re-implemented Annoy in 2D with some linear algebra maths. Then I spent some time going through some tutorial on vectors, and expanded the script to handle data in 3D and more. So instead of finding gradient, the perpendicular line in the middle of two points, I construct a plane, and find the distance between it and points to construct the tree.

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• Database transactions involving prepared statements

  I was thinking whether it is possible to avoid exposing PDO and PDOStatement objects to the users of my database library (mainly just me). While I was working on my project I sort of notice that there is a almost fixed pattern whenever I work with the database. With this in mind, I added in some new functions to the library, and decided to make a quick release for this.

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• Dragon Curve

  I really don’t know how to start explaining what is a Dragon Curve. However, I find it is interesting enough after finding out that there’s actually a fixed pattern of occurrence. Therefore I spent some time writing a series of scripts to plot the generated fractal into a graph. What I didn’t expect is, the series get really complicated after a while.

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• Building librdf-storage-virtuoso Package

  I wanted to try using virtuoso as the storage engine for Redland but unfortunately there is no librdf-storage-virtuoso package for Ubuntu. After getting some help from @dajobe, I attempted to build the packages myself. Although it takes quite some time to build packages, but not too difficult it seems.

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• Self-hosted photo album

  My cloud storage is nearly exploding, and I am not in a good position to start subscribing for more storage (Yes, I am still #opentowork). Considering I just moved my domain settings to Cloudflare and started using Cloudflare tunnel, I figure I probably should just back up some of my photos, and host it on my workstation.

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