June 2019
Beginner to intermediate
598 pages
12h 10m
English
Content preview from R Cookbook, 2nd Edition
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapter 15. Simple Programming
R lets you accomplish a lot without knowing anything about programming. Programming opens the door to accomplishing more, however, and most serious users eventually perform some level of programming, starting simply and possibly becoming quite proficient. While this is not a programming book, this chapter lays out some programming recipes that R users typically find useful to begin their journey.
If you are already familiar with programming and programming languages, a few notes here may help you quickly adapt. (If these terms are unfamiliar to you, you can skip this section.) Here are some technical details of R to be aware of:
- Typeless variables
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Variables in R do not have a fixed type, such as integer or character, unlike in typed languages such as C and Java. A variable could contain a number one moment and a data frame the next.
- Return values
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All functions return a value. Normally, a function returns the value of the last expression in its body. You can also use
return(expr)anywhere within the body. - Call-by-value parameters
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Function parameters are “call by value”—in other words, parameters are strictly local variables, and changes to those variables do not affect the caller’s value.
- Local variables
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You create a local variable simply by assigning a value to it. Explicit declaration is not required. When the function exits, local variables are lost.
- Global variables
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Global variables are held in the user’s workspace. Within a function ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.