52
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16
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I have a data frame called "newprice" (see below) and I want to change the column names in my program in R. &
62
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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
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30
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In R, mean() and median() are standard functions which do what you'd expect. mode() tells you the intern
57
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20
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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
526
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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
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13
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908
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I am in a process of figuring out how to use my university cluster. It has 2 versions of R installed. System w
56
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28
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691
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What tricks do people use to manage the available memory of an interactive R session? I use the functions bel
58
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11
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I have very large tables (30 million rows) that I would like to load as a dataframes in R. read.table() has a
58
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17
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I'm trying to initialize a data.frame without any rows. Basically, I want to specify the data types for e
63
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7
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I have a file, called a.r, it has a chmod of 755, sayHello <- function(){ print('hello') } s
59
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7
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46
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15
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710
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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
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24
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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
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12
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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
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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
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8
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What is the difference between require() and library()?
What is the difference between require() and library()?
53
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18
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825
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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
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11
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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
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16
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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
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11
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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.
