LVM: A Little Christmas Magic for Admins
Every Linux admin knows LVM, the Logical Volume Manager. This archived note summarises two advanced topics I had recently used: cloning logical volumes and caching a logical volume on an SSD.
Every Linux admin knows LVM, the Logical Volume Manager. This archived note summarises two advanced topics I had recently used: cloning logical volumes and caching a logical volume on an SSD.
At DevFest 2014 in Prague at CTU, I gave a talk about speech communication with computers and whether we actually want to talk to them. The archived post points readers to the recording.
This short article extends the previous post on parsing Wikipedia XML dumps. It shows a small piece of code for iterative XML loading with ElementTree, which is now part of the Python standard library.
This archived note is useful for anyone working in machine learning who needs to process large amounts of text from Wikipedia. It shows several pieces of Python code that help with extracting clean text from MediaWiki pages.
Python handles runtime errors with exceptions. This debugging post shows a Python 2.x trap where missing parentheses in an except clause can overwrite an exception name and make later exception handling behave incorrectly.
In several projects we used MongoDB for its flexible data representation. This archived technical note shows how to serve files stored in MongoDB GridFS through an HTTP server written in Python, including a Tornado StaticFileHandler-based approach.
In June and July 2014, I used the methods I had worked with in my dissertation in a Kaggle competition on multi-label classification of Greek media articles. The competition ran from 2 June to 15 July 2014 and ended with my model in third place out of 121 teams.
Regular expressions are popular among many programmers. This debugging article looks at what is wrong with the expression [+-0123456789] and why a minus sign inside a character class can change the whole meaning.
This debugging note only touches Python indirectly, but a Python Tornado server plays the main role. It describes a problem with proxying WebSockets through Apache and why HTTP subpaths had to be proxied explicitly before the WebSocket path.
Where did the bug probably happen? This typical debugging question opens a short series about Python bugs that look obvious only after they are found. The first example shows how a missing comma in a multiline tuple or list literal can lead to surprising behaviour.
Children's Day deserves a proper gift, and it is hard to beat the combination of sand and water. This first archived post from honzas.cz shows how I brought water to a playground with a sandbox and turned it into a shower, fountain, and slide accessory in one.