r Archives - Page 15 of 18

How do I install an R package from source?

A friend sent me along this great tutorial on webscraping The New York Times with R. I would really love to try it. ...

May 6, 2022
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How can two strings be concatenated?

How can I concatenate (merge, combine) two values? For example I have: tmp = cbind("GAD", "AB") tmp # [,1] [,2] #...

May 6, 2022
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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. After ...

May 5, 2022
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How to sum a variable by group

I have a data frame with two columns. First column contains categories such as “First”, “Second”, “Third”, and the second column has numbers ...

May 5, 2022
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How to write trycatch in R

I want to write trycatch code to deal with error in downloading from the web. url <- c( "http://stat.ethz.ch/R-manual/R-devel/library/base/html/connections.html", "http://en.wikipedia.org/wiki/Xz") y <- mapply(readLines, ...

May 5, 2022
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Changing column names of a data frame

I have a data frame called “newprice” (see below) and I want to change the column names in my program in R. > ...

May 5, 2022
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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, 453,435,324,34,456,56,567,65,34,435) How can I have R count the number of times a value x ...

May 5, 2022
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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 internal storage mode of the object, ...

May 5, 2022
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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 it’s ...

May 4, 2022
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