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DATA MINING
Desktop Survival Guide by Graham Williams |
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Testing Package Availability |
If a function you write depends on the functionality of some package,
such as gplots, use the stopifnot function
to exit if the package is not available:
myfun <- function()
{
stopifnot(require(gplots))
[...]
}
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Also, the .packages can be used to list all packages
that have been installed on your system:
> .packages(all=TRUE) [1] "acepack" "ada" "amap" [4] "arules" "bitops" "butler" [..] [73] "tcltk" "tools" "utils" [76] "mapdata" |
And a call to the library function with no arguments
will list all packages installed, and a one line description:
> library()
Packages in library '/usr/lib/R/library':
base The R Base Package
datasets The R Datasets Package
graphics The R Graphics Package
[...]
Packages in library '/usr/local/lib/R/site-library':
acepack ace() and avas() for selecting regression
transformations
ada Performs boosting algorithms for a binary
response
[...]
XML Tools for parsing and generating XML within R
and S-Plus.
xtable Export tables to LaTeX or HTML
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