The R language, for programmers
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The R language, for programmers
1–10 of 79 posts
Re: The R language, for programmers
#2I actually quite like the R language. A buddy of mine is in his University's PoliSci program and one of the requirements is to learn R for statistical and trend analysis. He could not stop complaining until I offered to help him learn it by learning it with him. After doing his first assignment, we were both impressed with what could be easily done in R to visualize data. I think he now realizes how useful of a tool R can be in his future career.
Re: The R language, for programmers
#3I'd like to see a detailed explanation of R's scoping. It's not just lexical scoping; callees can deliberately manipulate the scope their arguments are evaluated in, for example. So you can call a function and pass arguments that are available in local scope, but the arguments are lazily evaluated, and the callee might evaluate them in an entirely different scope.
Typically this is done for manipulating datasets. You might have a data frame with columns Width and Height, and so you want to be able to call do.stuff(Width, Height, data=foo), and have Width and Height automatically taken from within foo. But sometimes it crops up in unexpected places.
Re: The R language, for programmers
#4Why no discussion of dataframes? I find these to be the most useful aspect of R which I miss the most in other languages.
Re: The R language, for programmers
#5The biggest "gotcha" for learning R as a programmer is that R interprets character vectors of data frames as factor vectors by default, which will usually break something in your code.
If you're learning R, learn to use dplyr for data manipulation and ggplot2 for plotting. Both will save you a lot of time.
Re: The R language, for programmers
#6Why no discussion of dataframes? I find these to be the most useful aspect of R which I miss the most in other languages.
If you use Python, have you checked out Panda's dataframes? It's not quite the R experience, but pretty close plus you get all the benefits of the Python ecosystem.
Re: The R language, for programmers
#7I'd like to see a detailed explanation of R's scoping. It's not just lexical scoping; callees can deliberately manipulate the scope their arguments are evaluated in, for example. So you can call a function and pass arguments that are available in local scope, but the arguments are lazily evaluated, and the callee might evaluate them in an entirely different scope. Typically this is done for manipulating datasets. You…
Are you familiar with Hadley's Advanced-R book? You can buy a hardcopy, but it's free online: http://adv-r.had.co.nz
There's a section on lexical scoping, and lots of other non-basic stuff that is hard to find covered elsewhere at all, much less well. From what I've seen, this is absolutely the best reference for deep R stuff that exists.
Re: The R language, for programmers
#8R is one of those languages that looks like it was designed in a vacuum by a very smart person. It has many common, modern PL constructs, but they're expressed syntactically in a way that in no way resembles any other language I've seen. The entire syntactic legacy of Algol, Pascal, C, etc, all are thrown by the wayside. Familiarity with any of those syntaxes felt to me like more of a liability than a help. That's not to say that the concepts don't apply, just the syntax.
Re: The R language, for programmers
#9The biggest "gotcha" for learning R as a programmer is that R interprets character vectors of data frames as factor vectors by default , which will usually break something in your code. If you're learning R, learn to use dplyr for data manipulation and ggplot2 for plotting. Both will save you a lot of time.
Agreed, this was a huge pain point for me early on; I started setting the necessary option to force stringsAsCharacters rather than specifying that arg in read.csv everytime.
Edit: I had mentioned data.table as being better than dplyr for performance reasons, but it has a unique learning curve and isn't really good for beginners
Re: The R language, for programmers
#10I'd like to see a detailed explanation of R's scoping. It's not just lexical scoping; callees can deliberately manipulate the scope their arguments are evaluated in, for example. So you can call a function and pass arguments that are available in local scope, but the arguments are lazily evaluated, and the callee might evaluate them in an entirely different scope. Typically this is done for manipulating datasets. You…
Are you familiar with Hadley's Advanced-R book? You can buy a hardcopy, but it's free online: http://adv-r.had.co.nz There's a section on lexical scoping, and lots of other non-basic stuff that is hard to find covered elsewhere at all, much less well. From what I've seen, this is absolutely the best reference for deep R stuff that exists.
I've seen it but haven't read in depth. Now that I see the scoping section I'll have to read through it.