R
R is a free, open-source programming language and software environment for statistical computing, bioinformatics, visualization and general computing. Provide minimal, reproducible, representative example(s) with your questions. Use dput() for data and specify all non-base packages with library calls. Do not embed pictures for data or code, use indented code blocks.
62
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9
answers
1.7K
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Check existence of directory and create if doesn't exist
I often find myself writing R scripts that generate a lot of output. I find it cleaner to put this output into
57
votes
30
answers
2.1K
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How to find the statistical mode?
In R, mean() and median() are standard functions which do what you'd expect. mode() tells you the intern
57
votes
20
answers
1.6K
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Counting the number of elements with the values of x in a vector
I have a vector of numbers: numbers <- c(4,23,4,23,5,43,54,56,657,67,67,435, 453,435,324,34,456,5
57
votes
8
answers
528
views
Cluster analysis in R: determine the optimal number of clusters
Being a newbie in R, I'm not very sure how to choose the best number of clusters to do a k-means analysis
61
votes
13
answers
911
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How to find out which package version is loaded in R?
I am in a process of figuring out how to use my university cluster. It has 2 versions of R installed. System w
56
votes
28
answers
694
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Tricks to manage the available memory in an R session
What tricks do people use to manage the available memory of an interactive R session? I use the functions bel
58
votes
11
answers
2.7K
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Quickly reading very large tables as dataframes
I have very large tables (30 million rows) that I would like to load as a dataframes in R. read.table() has a
58
votes
17
answers
2.1K
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Create an empty data.frame
I'm trying to initialize a data.frame without any rows. Basically, I want to specify the data types for e
63
votes
7
answers
2.7K
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Run R script from command line
I have a file, called a.r, it has a chmod of 755, sayHello <- function(){ print('hello') } s
59
votes
7
answers
2.1K
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46
votes
15
answers
712
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Drop unused factor levels in a subsetted data frame
I have a data frame containing a factor. When I create a subset of this dataframe using subset or another inde
67
votes
24
answers
2.5K
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Convert a list to a data frame
I have a nested list of data. Its length is 132 and each item is a list of length 20. Is there a quick way to
49
votes
12
answers
2.6K
views
The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or dataframe
R provides two different methods for accessing the elements of a list or data.frame: [] and [[]]. What is the
57
votes
12
answers
2.6K
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How to unload a package without restarting R
I'd like to unload a package without having to restart R (mostly because restarting R as I try out differ
57
votes
8
answers
2.2K
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What is the difference between require() and library()?
What is the difference between require() and library()?
53
votes
18
answers
828
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How should I deal with "package 'xxx' is not available (for R version x.y.z)" warning?
I tried to install a package, using install.packages("foobarbaz") but received the warning Warning message
44
votes
11
answers
1.1K
views
How can I view the source code for a function?
I want to look at the source code for a function to see how it works. I know I can print a function by typing
57
votes
16
answers
2.3K
views
Plot two graphs in same plot in R
I would like to plot y1 and y2 in the same plot. x <- seq(-2, 2, 0.05) y1 <- pnorm(x) y2 <- pnorm(x
61
votes
11
answers
1.1K
views
How to convert a factor to integer umeric without loss of information?
When I convert a factor to a numeric or integer, I get the underlying level codes, not the values as numbers.
62
votes
7
answers
2.4K
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How can we make xkcd style graphs?
Apparently, folk have figured out how to make xkcd style graphs in Mathematica and in LaTeX. Can we do it in R