Stack Overflow
Stack Overflow

Questions tagged [r]

R is a free, open-source programming language & software environment for statistical computing, bioinformatics, visualization & general computing. Please use minimal reproducible examples others can run using copy & paste. Show desired output entirely. Use dput() for data & specify all non-base packages with library(). Don't embed pictures for data or code, use indented code blocks instead. For statistics questions, use https://stats.stackexchange.com.

R Programming Language

R is a free, open-source programming language and software environment for statistical computing, bioinformatics, information graphics, and general computing. It is a multi-paradigm language and dynamically typed. R is an implementation of the S programming language combined with lexical scoping semantics inspired by Scheme. R was created by Ross Ihaka and Robert Gentleman and is now developed by the R Development Core Team. The R environment is easily extended through a packaging system on CRAN, the Comprehensive R Archive Network.

Scope of questions

This tag should be used for programming-related questions about R. Including a minimal reproducible example in your question will increase your chances of getting a timely, useful answer. Questions should not use the tag unless they relate specifically to the RStudio interface and not just the R language.

If your question is more focused on statistics or data science, use Cross Validated or Data Science, respectively. Bioinformatics-specific questions may be better received on Bioconductor Support or Biostars. General questions about R (such as requests for off-site resources or discussion questions) are unsuitable for Stack Overflow and may be appropriate for one of the general, or special-interest, R mailing lists.

Please do not cross-post across multiple venues. Do research (read tag wikis, look at existing questions, or search online) to determine the most appropriate venue so that you have a better chance of receiving solutions to your question. Your question may be automatically migrated to a more appropriate Stack Exchange site. If you receive no response to your questions after a few days, or if your question is put on hold for being off-topic, it is then OK to post to another venue, giving a link to your Stack Overflow question - but don't cross-post just because your question is down-voted or put on hold for being unclear. Instead, work on improving your question.

Stack Overflow resources

Official CRAN Documentation

Other CRAN resources

Free Resources

Interactive R learning

  • Coursera - Learn how to use R for effective data analysis
  • DataCamp - Many interactive R and data science courses
  • Dataquest - Interactive R courses for data science
  • edX - Basic Statistics and R (basic course, not just for life sciences)
  • edX - Introduction to R Programming
  • R-exercises - 1000+ R exercises and solutions
  • RPubs - Easy web publishing from R
  • Swirl - R-package to learn R interactively

Free books on R:

Programming Chrestomathy (problems written in many languages)

Other free resource materials

IDEs and editors for R

Web application framework for R

  • Shiny - Turn your analyses into interactive web applications. No HTML, CSS, or JavaScript knowledge required.
  • FastRWeb - Fast Interactive Web Framework for Data Mining Using R

Graphical User Interfaces (GUI) in R

Code style guides

Other Resources

Recommended additional R resources include:

Alternative R engines

All alternative R engines have the goal of increasing R's performance and memory management.

Downstream distributions with complete compatibility

Forks of R with near 100% code compatibility

  • pqR by Radford Neal (C-based).
  • Rho by Karl Millar, based upon CXXR by Andrew Runnalls (C++-based). The development on Rho has been suspended indefinitely.

Rewrites with high code compatibility

  • Renjin by BeDataDriven (Java-based).
  • TERR by Tibco (C++-based).

Experimental and early-stage rewrites

  • Riposte by Justin Talbot (C++-based).
  • FastR by Jan Vitek and Tomas Kalibera (Java-based).

Unrelated tags

Due to R's simple name, questions sometimes get tagged with the tag when a different topic is meant. Here is a list of tags that mistagged R questions might be re-tagged to

  • for questions related to the file R.java on
  • "A command line tool for running JavaScript scripts that use the Asynchronous Module Definition API (AMD) for declaring and using JavaScript modules and regular JavaScript script files. It is part of the RequireJS project, and works with the RequireJS implementation of AMD." (from the wiki summary)
  • for questions related to RStudio use the rstudio tag. Don't use this tag just because you are working with RStudio.
496613 questions
331
votes
18 answers

ggplot with 2 y axes on each side and different scales

I need to plot a bar chart showing counts and a line chart showing rate all in one chart, I can do both of them separately, but when I put them together, I scale of the first layer (i.e. the geom_bar) is overlapped by the second layer (i.e. the…
lokheart
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328
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1 answer

Remove all of x axis labels in ggplot

I need to remove everything on the x-axis including the labels and tick marks so that only the y-axis is labeled. How would I do this? In the image below I would like 'clarity' and all of the tick marks and labels removed so that just the axis line…
Vedda
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324
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5 answers

Difference between Boolean operators && and & and between || and | in R

According to the R language definition, the difference between & and && (correspondingly | and ||) is that the former is vectorized while the latter is not. According to the help text, I read the difference akin to the difference between an "And"…
Suraj
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323
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16 answers

How to import multiple .csv files at once?

Suppose we have a folder containing multiple data.csv files, each containing the same number of variables but each from different times. Is there a way in R to import them all simultaneously rather than having to import them all individually? My…
Jojo
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318
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14 answers

Combine two data frames by rows (rbind) when they have different sets of columns

Is it possible to row bind two data frames that don't have the same set of columns? I am hoping to retain the columns that do not match after the bind.
Btibert3
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318
votes
18 answers

How to convert a data frame column to numeric type?

How do you convert a data frame column to a numeric type?
acroa
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316
votes
8 answers

Remove an entire column from a data.frame in R

Does anyone know how to remove an entire column from a data.frame in R? For example if I am given this data.frame: > head(data) chr genome region 1 chr1 hg19_refGene CDS 2 chr1 hg19_refGene exon 3 chr1 hg19_refGene CDS 4 chr1…
Nanami
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315
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8 answers

YAML current date in rmarkdown

I'm wondering if there's a trick to put the current date in the YAML front-matter of a .rmd document to be processed by knitr and the rmarkdown package. I used to have the following line at the top of my wiki pages, _baptiste, `r…
baptiste
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314
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3 answers

How to properly document S4 class slots using Roxygen2?

For documenting classes with roxygen(2), specifying a title and description/details appears to be the same as for functions, methods, data, etc. However, slots and inheritance are their own sort of animal. What is the best practice -- current or…
Paul 'Joey' McMurdie
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314
votes
10 answers

Update R using RStudio

How can I update R via RStudio?
AdamNYC
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313
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10 answers

Add regression line equation and R^2 on graph

I wonder how to add regression line equation and R^2 on the ggplot. My code is: library(ggplot2) df <- data.frame(x = c(1:100)) df$y <- 2 + 3 * df$x + rnorm(100, sd = 40) p <- ggplot(data = df, aes(x = x, y = y)) + geom_smooth(method =…
MYaseen208
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307
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10 answers

How do I delete rows in a data frame?

I have a data frame named "mydata" that looks like this this: A B C D 1. 5 4 4 4 2. 5 4 4 4 3. 5 4 4 4 4. 5 4 4 4 5. 5 4 4 4 6. 5 4 4 4 7. 5 4 4 4 I'd like to delete row 2,4,6. For example, like this: …
R newbie
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306
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6 answers

Why are these numbers not equal?

The following code is obviously wrong. What's the problem? i <- 0.1 i <- i + 0.05 i ## [1] 0.15 if(i==0.15) cat("i equals 0.15") else cat("i does not equal 0.15") ## i does not equal 0.15
dplanet
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304
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5 answers

Filter rows which contain a certain string

I have to filter a data frame using as criterion those row in which is contained the string RTB. I'm using dplyr. d.del <- df %>% group_by(TrackingPixel) %>% summarise(MonthDelivery = as.integer(sum(Revenue))) %>% …
Gianluca
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303
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23 answers

How to change facet labels?

I have used the following ggplot command: ggplot(survey, aes(x = age)) + stat_bin(aes(n = nrow(h3), y = ..count.. / n), binwidth = 10) + scale_y_continuous(formatter = "percent", breaks = c(0, 0.1, 0.2)) + facet_grid(hospital ~ .) +…
wishihadabettername
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