R in a Nutshell

Listing Packages in Local Libraries

To get the list of packages loaded by default, you can use the getOption command to check the value of the defaultPackages value:

> getOption("defaultPackages")
[1] "datasets"  "utils"     "grDevices" "graphics"  "stats"    
[6] "methods"

This command omits the base package; the base package implements many key features of the R language and is always loaded.

If you would like to see the list of currently loaded packages, you can use the .packages command (note the parentheses around the outside):

> (.packages())
[1] "stats"     "graphics"  "grDevices" "utils"     "datasets"  "methods"  
[7] "base"

To show all packages available, you can use the all.available option with the packages command:

> (.packages(all.available=TRUE))
 [1] "KernSmooth" "MASS"       "base"       "bitops"     "boot"      
 [6] "class"      "cluster"    "codetools"  "datasets"   "foreign"   
[11] "grDevices"  "graphics"   "grid"       "hexbin"     "lattice"   
[16] "maps"       "methods"    "mgcv"       "nlme"       "nnet"      
[21] "rpart"      "spatial"    "splines"    "stats"      "stats4"    
[26] "survival"   "tcltk"      "tools"      "utils"

You can also enter the library() command with no arguments and a new window will pop up showing you the set of available packages.

Included Packages

R comes with a number of different packages (see Table 4-1 for a list). Some of these packages (like base, graphics, grDevices, methods, and utils) implement basic features of the R language or R environment. Other packages provide commonly used statistical modeling tools (like cluster, nnet, and stats). Other packages implement ...