Ragu Pappu Technical thoughts, mostly

Interactive Dublin (California) Weather Visualization Using Shiny

A few weeks back I wrote a post in which I visualized Dublin (CA) 2014 weather in Edward Tufte's style of New York 2003 weather visualization. That post used a dataset containing 15 years of daily weather data from 2000 to 2014 and showed daily temperature highs and lows against a background of daily record highs and lows and average highs and lows of years before 2014. I wanted to write an interactive application using Shiny, RStudio's web application framework for R, and the Dublin weather visualization seemed like a great candidate. I wrote the Shiny app and in the chart below you see the app in action -- an interactive version of that visualization. The user can select the range of years of temperature data to form the background, anywhere between years 2000 and 2014 inclusive.

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How I Set Up My Website Using GitHub Pages and Jekyll

I had been thinking of spiffying up my plain-looking WordPress-hosted blog for some time now and a few days back I got to do just that. Actually I did more than that: I ended up building a brand new website! While searching online for the how-tos I discovered GitHub Pages and Jekyll. GitHub Pages allows you to host your website for free and Jekyll lets you build static websites. It costs me ~$50 per year to host my blog on Wordpress so the free hosting on GitHub sounded like a great deal. On top of it the Jekyll website generator would allow the look and feel of the blog — the whole design — to be completely under my control. And so I took on the project. The project required git which was already installed on my desktop PC.

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Dublin (California) 2014 Weather Using R

In the data visualization community Edward Tufte's chart of New York City 2003 weather is well-known. A few weeks ago Brad Boehmke published a blogpost with a similar chart for his city, Dayton, titled Dayton's weather in 2014 which inspired me to do a similar visualization for my city, Dublin, California. The result is the chart below. The R code to build the chart is located here and it draws from Boehmke's post but also includes original code. Further below I describe the steps used to arrive at the chart. Dublin 2014 Weather testing

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DIY: Desktop PC Using Shuttle DS81 Barebone PC System

I needed to run a 64-bit Virtual Machine on my laptop when I found out that it did not support virtualization even though it had a 64-bit CPU. That got me started on acquiring a new PC. I decided that I wanted a mid-to-high-end PC -- not quite a high-end gaming PC -- but one with sufficient horsepower to be able to run multi-threaded applications with ease. I settled on the following minimum configuration: a 64-bit CPU with hardware support for virtualization, 8GB RAM, and 256GB hard drive. Superior graphics performance was not on my list of must-haves.

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Cloudera Hadoop Developer Training – My experience

Last week (Nov 11-14) I attended the Cloudera Developer Training for Apache Hadoop course and in this post I share my experience and takeaways from that training. But first, a brief bit about me to lay out the context for my experience with this training. I have worked in the Telecommunications industry and have several years experience with Embedded Systems software design and development and about 2 months ago I decided to work in the Big Data space, which led me to this training course.

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