My name is Eric Johnson. I live in Boulder, Colorado.

I wrote this site to help me:

Present some portfolio items.

Learn more about programming, math, machine learning and data science.

Get more practice presenting information and techniques to other humans.

Discover and present things about the world using analytic methods.

This site will be focused on applications related to data science. Right now though the content is more typically numerical analysis. First I have a bunch of algorithms, proofs, and interesting problems to post related to numerical PDEs, linear algebra and dynamics.

Tools:

R: my default programming environment for mathematics.

Python: a very useful programming language! I like to use Python for Machine Learning applications and for code that needs to scale well.

Matlab: an excellent program for doing work with vectors and matrices. My graduate work was written in Matlab - so it is one of the languages I am most comfortable using.

Mathematica: excellent for a variety of things. The symbolic math functionality in Mathematica is unparalleled. The Mathematica language also excels at producing great web applications. Check out http://demonstrations.wolfram.com/

Sympy: An amazing symbolic math library for Python. I will post some things done with it soon.

LaTeX: the ONLY way to get mathematics to print correctly. If you are serious about producing professional-looking mathematics, LaTeX is easy to use and incredibly powerful.

MathJax: used to render math on this site. The math is actually written in LaTeX.

yED : a very nice program for creating graphs.

Fluke 87v: my default digital multimeter.

Amprobe 54-NAV: my ammeter. Also a digital multimeter. Useful and trustworthy but not as accurate as the Fluke 87v.

Rigol DS1054Z: oscilloscope. This is probably the best-in-class for oscilloscopes that are less than $1000.

Digilent Analog Discovery Kit a really nice USB oscilloscope I bought while a graduate student. I'm using it now as a function generator.

Solidworks: my tool of choice for design.

Kubuntu: my default programming environment. It is Ubuntu with a KDE interface. I also use a Macbook pro and a win 7 machine - but I don't like programming on Windows (No Bash shell?!?!).

The reason for the electrical equipment being listed here will become clear as I post more items. I often use the oscilloscope to turn continuous electrical information into a dataset. For example, I'll be posting an analysis of what a 'TENS' unit (one of those electrical shock medical things) does. Multimeters and oscilloscopes are crucial for doing any serious electrical engineering experiments or troubleshooting equipment.

About me:

I am a numerical analyst turned data cruncher. I have a bachelors of arts in Computational Linguistics from The Ohio State University. I have a Masters Of Science in Applied Mathematics from Washington State University. My advisor was Dr. Kevin Cooper. My graduate work involved performing numerical analysis on a nonlinear particle physics problem. I work on 'critical systems' at the IBM facility in Boulder, Colorado.

Some of my other interests include music composition, photography, design and electric guitars.