Monday, September 9, 2013

Installing large number of packages in R - method 2

In one my previous blog, I discussed a method for installing multiple R packages from one version in another.  In the post, I used a combination of R and Python.  In this post, I will present a method that uses only R.

There are two functions in the file (listed below), listmultipack and installmultipack.  You can copy the content of the listing below and name it 'packageinstall.r'.

The function, listmultipack reads the list of all packages in a given version and writes them to a file. The default file name is 'requirements.txt'.  The name has been chosen to follow the Python convention.  Alternately, you can name it to any other file name.

Once the new R version is installed on the same machine or a different machine, the installmultipack function can be used to install all the packages in the 'requirements.txt' or the file name that you chose.  Finally the function prints all warnings that were generated during the installation.

To use the file, at the R command prompt, you need to load the file using

>> source("packageinstall.r")

To obtain the list of packages on to file 'mylist.txt', type

>> listmultipack('mylist.txt')

To install all the packages in the mylist.txt file, type

>> installmultipack('mylist.txt')

Alternately, if you do not have a previous installation of R and would like to install multiple R packages using one command, you can also create a requirements file by listing the package names in a text file.  Each package name should be in a line by itself.