A few days ago a friend asked me the following question: how to efficiently extract some specific lines from a large text file, possibily compressed by Gzip? He mentioned that he tried some R functions such as read.table(skip = ...), but found that reading the data was too slow. Hence he was looking for some alternative ways to extracting the data. This is a common task in preprocessing large data sets, since in data exploration, very often we want to peek at a small subset of the whole data to gain some insights.

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This semester I’m taking a course in big data computing using Scala/Spark, and we are asked to finish a course project related to big data analysis. Since statistical modeling heavily relies on linear algebra, I investigated some existing libraries in Scala/Java that deal with matrix and linear algebra algorithms. 1. Set-up Scala/Java libraries are usually distributed as *.jar files. To use them in Scala, we can create a directory to hold them and set up the environment variable to let Scala know about this path.

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Dr. Hadley Wickham is the Chief Scientist of RStudio and Assistant Professor of Statistics at Rice University. He is the developer of the famous R package ggplot2 for data visualization and the author of many other widely used packages like plyr and reshape2. On Sep 13, 2013 he gave a talk at Department of Statistics, Purdue University, and later I (Yixuan) had a conversation with him (Hadley), talking about his own experience and interest on data visualization, data tidying, R programming and other related topics.

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Yixuan Qiu

Statistics, Data, and Programming

Associate Professor