## Unit conversions with Python and Pint

Units and unit conversions are BIG in engineering. Engineers solve the world's problems in teams. Any problem that is solved has to have a context that it is solved in. How heavy can a rocket be and still make it off the ground? What thickness body panels should be used to keep occupants save during a crash? In engineering, a number without a unit is like a fish without water. It just flops around hopelessly without context and is useless. How can we get help using units? Programming is one way. In this post, we are going to use Python and Pint, a python package used for unit conversions, to do a couple of sample unit conversion problems.

## Bar charts with error bars using Python and matplotlib

Bar charts with error bars are useful in engineering to show the confidence or precision in a set of measurements or calculated values. Bar charts without error bars give the illusion that a measured or calculated value is known to high precision or high confidence. In this post, we will build a bar plot using Python and matplotlib. The plot will show the coefficient of thermal expansion (CTE) of three different materials based on a small data set. Then we'll add error bars to this chart based on the standard deviation of the data.

## Unicode characters for engineers in Python

Unicode characters are very useful for engineers. A couple commonly used symbols in engineers include Omega and Delta. We can print these in python using unicode characters. From the Python interpreter we can type:

>>> print('Omega: \u03A9')
Omega: Ω
>>> print('Delta: \u0394')
Delta: Δ
>>> print('sigma: \u03C3')
sigma: σ
>>> print …

## Python Virtual Environments in OS X, Linux and Windows 10

In this post, I'll review creating virtual environments on three different operating systems: Windows 10, Linux and Mac OSX. Using virtual environments is good programming practice when using Python. A virtual environment will separate the Python interpreter and installed modules from the main Python installation.

## How I Build This Site - Part 7

This is the seventh part of a multi-part series on how I built this site. In last post, we added two new pages to our site. An About page and a Book page. In this post, we are going to deploy the site to github pages. Github pages is a place on GitHub.com were documentation and static sites can be hosted.