book

The AWK Programming Language, 2nd Edition

by Alfred V. Aho, Brian W. Kernighan, Peter J. Weinberger

September 2023

Intermediate to advanced

240 pages

7h 40m

English

Addison-Wesley Professional

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Organization of the BookThe ExamplesEvolution of AwkAcknowledgmentsAcknowledgments for the First Edition
1.1 Getting Started1.2 Simple Output1.3 Formatted Output1.4 Selection1.5 Computing with Awk1.6 Control-Flow Statements1.7 Arrays1.8 Useful One-liners1.9 What Next?
2.1 Personal Computation2.2 Selection2.3 Transformation2.4 Summarization2.5 Personal Databases2.6 A Personal Library2.7 Summary

3.1 The Sinking of the Titanic3.2 Beer Ratings3.3 Grouping Data3.4 Unicode Data3.5 Basic Graphs and Charts3.6 Summary
4.1 Data Transformation and Reduction4.2 Data Validation4.3 Bundle and Unbundle4.4 Multiline Records4.5 Summary
5.1 Generating Reports5.2 Packaged Queries and Reports5.3 A Relational Database System5.4 Summary
6.1 Random Text Generation6.2 Interactive Text-Manipulation6.3 Text Processing6.4 Making an Index6.5 Summary
7.1 An Assembler and Interpreter7.2 A Language for Drawing Graphs7.3 A Sort Generator7.4 A Reverse-Polish Calculator7.5 A Different Approach7.6 A Recursive-Descent Parser for Arithmetic Expressions7.7 A Recursive-Descent Parser for a Subset of Awk7.8 Summary
8.1 Sorting8.2 Profiling8.3 Topological Sorting8.4 Make: A File Updating Program8.5 Summary
9.1 Awk as a Language9.2 Performance9.3 Conclusion
A.1 PatternsA.2 ActionsA.3 User-Defined FunctionsA.4 OutputA.5 InputA.6 Interaction with Other ProgramsA.7 Summary

Content preview from The AWK Programming Language, 2nd Edition

3 Exploratory Data Analysis

The previous chapter described a number of small scripts for personal use, often idiosyncratic or specialized. In this chapter, we’re going to do something that is also typical of how Awk is used in real life: we’ll use it along with other tools to informally explore some real data, with the goal of seeing what it looks like. This is called exploratory data analysis or EDA, a term first used by the pioneering statistician John Tukey.

Tukey invented a number of basic data visualization techniques like boxplots, inspired the statistical programming language S that led to the widely-used R language, co-invented the Fast Fourier Transform, and coined the words “bit” and “software.” The authors knew John Tukey as a friend ...