Posted in 2021

Fuel Tracker

I have written a simple fuel tracker application and you can find it here. The idea is a simple system to keep track of fuel records far various vehicles I have owned through the years. I have been keeping track of my fuel records since 2002 across 4 vehicles. I have over 800 records stored in the database. A modest amount, but good information.

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LED Strip Calculations

The idea is to construct a spiral (Archimedean spiral or others) around a right-cone simulating a Christmas tree. We want to model the situation and understand how many lights or how long the strip(s) should be to wrap the proper amount of loops around the tree. This blog will establish the basic model and mathematics. This article will walk you through the mathematical derivation and the calculations. The derivations are for completeness. An understanding of the process is not required to use the results.

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Configure Git Bash on Windows to run Make

I have developed a Python template repository that contains a number of makefiles for managing repositories. Among the tasks, it can help with constructing virtual environments ($ make venv) and installing all pip dependencies. It can optionally launch Jupyter notebooks ($ make launch). The real power comes from the fact that I can use the same set of commands for the basic management of the Python repositories. It is really very handy on Linux. I do development work on windows and I wanted to be able to use the makefiles there. Unfortunately, there wasn’t an easy way that I really liked. There are options like Cygwin and even WSL for Windows. Both of these options were too heavy to do what I wanted.

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Cribbage Strategies Are Explored With New Code And New Methods

This is a rewrite of my previous cribbage article and my article on expected average. It also includes access to completely re-written code. The code is simplified and complete with unit tests. It uses the click library to drive a nice command line/terminal application. This article will assume you are familiar with the rules and the point counting conventions of cribbage. Some of the relevant counting and conventions will be reviewed.

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Vector Reflection (2D Derivation)

This notebook will work through the explanation of determining the 2D vector reflection from a surface. I had a problem where I needed to determine the reflected vector from an incident vector in two dimensions. There are a lot of pages out there with good explanations. But a lot of seemingly conflicting information caused me to question my knowldge and write this article. This source is quite nice. It walks you through the steps and develops a valid relationship:

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Circle/Ray Intersection

The problem: We have a 2D circle and we have a ray or line. What are the intersections points between the two, if any?

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Extract Email

I have a lot of alerts configured with Google Scholar for various research interests. It’s a very cool concept, setting up a keyword search like blast fragmentation shockwave and Google sending you a summary email of new research that matches.

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Updated on 2021-08-01

New update generated.

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Parts of Hashes and Expected Collisions

I am building a documentation system that works using Markdown for the documents and Pandoc to transform the documents to HTML, PDF, etc… It works well and is very easy to use. However there is a problem I have encountered. By default when Pandoc transforms a Markdown file to HTML, it automatically inserts section anchors. In Markdown, an ATX section header could look something like this:

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Measurement Uncertainty - How do measurement errors add up when working with areas?

Typically when you measure things, there is a certain amount of error. In everyday life, this is ignored for the most part. I was thinking about uncertainty in measuring areas. Like everyone else, I learned about uncertainty in measurement in high school during science class. It was further reinforced in university in every lab I took. The problem was, it was addressed as a set of rules to memorize and apply that covered the use of significant figures. Most people do not fully explore what this means exactly and consequently have trouble with the concept outside the typical canned responses. I was having trouble understanding why calculating an area with uncertainty was expressed the way it was.

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Cleaning Thunderbird Linked to Gmail IMAP Account

I was running backups on my system (Ubuntu 20.04) and realized that my ~/.thunderbird folder was huge. It was about 10 GB in size! That is a bit too much for my liking. I use Gmail as my primary provider. There were a lot of emails (over 50,000) stored on the server. I wanted to organize and move them offline to free up space. Why? Google has always touted that you shouldn’t have to delete anything. Well, I have email going back to 2004, and with Google’s announcement about photos I figured now was the time to free up space.

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