{"id":21440,"date":"2023-02-15T09:39:49","date_gmt":"2023-02-15T09:39:49","guid":{"rendered":"https:\/\/www.booksofall.com\/cn\/?post_type=product&p=21440"},"modified":"2023-02-15T09:39:50","modified_gmt":"2023-02-15T09:39:50","slug":"ad-hoc-data-analysis-from-the-unix-command-line","status":"publish","type":"product","link":"https:\/\/www.booksofall.com\/cn\/ad-hoc-data-analysis-from-the-unix-command-line\/","title":{"rendered":"Ad Hoc Data Analysis From The Unix Command Line"},"content":{"rendered":"

Unix\u00a0is a family of\u00a0multitasking<\/a>,\u00a0multiuser<\/a>\u00a0computer\u00a0operating systems<\/a>\u00a0that derive from the original\u00a0AT&T<\/a> Unix, whose development started in 1969\u00a0<\/sup>at the\u00a0Bell Labs<\/a>\u00a0research center by\u00a0Ken Thompson<\/a>,\u00a0Dennis Ritchie<\/a>, and others.<\/sup><\/p>\n

Initially intended for use inside the\u00a0Bell System, AT&T\u00a0licensed\u00a0Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including\u00a0University of California, Berkeley\u00a0(BSD),\u00a0Microsoft\u00a0(Xenix),\u00a0Sun Microsystems\u00a0(SunOS\/Solaris),\u00a0HP\/HPE\u00a0(HP-UX), and\u00a0IBM\u00a0(AIX). In the early 1990s, AT&T sold its rights in Unix to\u00a0Novell, which then sold the UNIX trademark to\u00a0The Open Group, an industry consortium founded in 1996. The Open Group allows the use of the mark for certified operating systems that comply with the\u00a0Single UNIX Specification\u00a0(SUS).<\/p>\n

Once upon a time, I was working with a colleague who needed to do some quick data analysis to get a handle on the scope of a problem. He was considering importing the data into a database or writing a program to parse and summarize that data. Either of these options would have taken hours at least, and possibly days. I wrote this on his whiteboard:<\/p>\n

\n
Your friends: cat, find, grep, wc, cut, sort, uniq<\/dd>\n<\/dl>\n

These simple commands can be combined to quickly answer the kinds of questions for which most people would turn to a database<\/a>, if only the data were already in a database. You can quickly (often in seconds) form and test hypotheses about virtually any record-oriented data source.<\/p>\n

Intended audience<\/span><\/h5>\n

You’ve logged into a Unix<\/a> box of some flavor and run some basic commands like\u00a0ls<\/tt>\u00a0and\u00a0cd<\/tt>\u00a0and\u00a0cat<\/tt>. If you don’t know what the\u00a0ls<\/tt>\u00a0command does, you need a more basic introduction to Unix than I’m going to give here.<\/p>\n","protected":false},"excerpt":{"rendered":"