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Sorting Big Data Big Data was a common buzzword in industry in 2012 until 2017. It is still common, but hopefully less of a buzzword. Now other buzzwords are more common: trends.embed.renderExploreWidget("TIMESERIES", {"comparisonItem":[{"keyword":"/m/0bs2j8q","geo":"","time":"2008-01-01 2020-03-24"},{"keyword":"/m/01hyh_","geo":"","time":"2008-01-01 2020-03-24"},{"keyword":"/m/0138n0j1 … Read More »

Python EEL Eel is a little Python library for making simple Electron-like offline HTML/JS GUI apps, with full access to Python capabilities and libraries. Hello World As a hello world example, I decided to create an offline version of write-math.com. Write-math in eel is on GitHub. The directory structure of … Read More »

Python is interpreted Python is interpreted. Python is a scripting language. I hear those two statements pretty often when people want to say that Python is slow or that Python is not suited for large systems. In this article I want to dispel those myths. Interpreted Language What does it mean to say … Read More »

Python Requirements Pythons package management is a constant source of confusion. One part of the confusion is in which format dependencies should get denoted. It gets worse, because there are too many tools. xkcd shows this pretty well: xkcd The Python environmental protection agency wants to seal it in a cement chamber … Read More »

Naming Styles Naming styles are one of the trivial things in a style guide. Here are some of then names you might hear. The Styles snake_case camelCase: Also lowerCamelCase PascalCase: Also UpperCamelCase CONSTANT_CASE: This is used in many languages for constants cebab-case: I have only seen this within strings. This is likely … Read More »

XOR XOR is a simple bit-wise defined function: \begin{align} \text{XOR}:& \{0, 1\} \times \{0, 1\} \rightarrow \{0, 1\}\\ \text{XOR}(a, b) :&= \begin{cases}0 &\text{if } a= b\\1&\text{otherwise}\end{cases} \end{align} To make it more convenient, we define \(a \oplus b := \text{XOR}(a … Read More »

MongoDB MongoDB is a document-oriented database system. It is used to store JSON objects. The problem it solves is working with heterogenous data which does not fit into a schema or where creating a schema would be overly complicated. If it fits into a schema, use a SQL database like MySQL … Read More »

File Encryption I recently wondered how difficult it is to encrypt a file. In this article I will show you two ways to do it. I use a text file content.txt with the content This is a top secret message! Don't show it to others! Applications GNU Privacy Guard (GnuPG or … Read More »

asyncio asyncio is a library to write concurrent code using the async/await syntax. Concurrency Basics Parallel vs Interleaved Running things concurrently means to run them at the same time. There are two ways to run stuff concurrently: In parallel or interleaved. The following images show the difference for compute-bound two … Read More »

Maximum Contiguous Subarray Sum The maximum contiguous subarray sum problem is one of the classics. Given an 1D array of numbers \(a_1, \dots, a_n\) with \(a_i \in \mathbb{R}\), find \(s\) such that: $$\exists l, r \in [1, \dots, n]: \forall p, q \in [1, \dots, n]: \sum_{i=p}^q \leq \sum_{i … Read More »