detach all packages while working in R

Question

While working to solve another problem I got this problem:

I can remove all R objects by:

rm(list = ls(all = TRUE))

Is there equivalent command that can detach installed packages during working session?

> sessionInfo()
R version 2.12.2 (2011-02-25)
Platform: i386-pc-mingw32/i386 (32-bit)

locale:
[1] LC_COLLATE=English_United States.1252 
[2] LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base 

require(ggplot2)

Loading required package: ggplot2
Loading required package: reshape
Loading required package: plyr

Attaching package: 'reshape'

The following object(s) are masked from 'package:plyr':

    round_any

Loading required package: grid
Loading required package: proto

sessionInfo()

R version 2.12.2 (2011-02-25)
Platform: i386-pc-mingw32/i386 (32-bit)

locale:
[1] LC_COLLATE=English_United States.1252 
[2] LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

attached base packages:
[1] grid      stats     graphics  grDevices utils     datasets  methods  
[8] base     

other attached packages:
[1] ggplot2_0.8.9 proto_0.3-9.1 reshape_0.8.4 plyr_1.4 

I tried this way, although even it worked in not a global solution :

pkg <- c("package:ggplot2_0.8.9", "package:proto_0.3-9.1", "package:reshape_0.8.4",  "package:plyr_1.4")

 detach(pkg, character.only = TRUE)

Error in detach(pkg, character.only = TRUE) : invalid 'name' argument
In addition: Warning message:
In if (is.na(pos)) stop("invalid 'name' argument") :
  the condition has length > 1 and only the first element will be used

What I am loking for is something global like:

  rm(list = ls(all = TRUE))

for objects, expect it would not remove attached base packages

thanks;

Answer 1

So, someone should have simply answered the following.

lapply(paste('package:',names(sessionInfo()$otherPkgs),sep=""),detach,character.only=TRUE,unload=TRUE)

(edit: 6-28-19) In the latest version of R 3.6.0 please use instead.

invisible(lapply(paste0('package:', names(sessionInfo()$otherPkgs)), detach, character.only=TRUE, unload=TRUE))

Note the use of invisible(*) is not necessary but can be useful to prevent the NULL reply from vertically spamming the R window.

Answer 2

Please try this:

detachAllPackages <- function() {

  basic.packages <- c("package:stats","package:graphics","package:grDevices","package:utils","package:datasets","package:methods","package:base")

  package.list <- search()[ifelse(unlist(gregexpr("package:",search()))==1,TRUE,FALSE)]

  package.list <- setdiff(package.list,basic.packages)

  if (length(package.list)>0)  for (package in package.list) detach(package, character.only=TRUE)

}

detachAllPackages()

Answer 3

You were close. Note what ?detach has to say about the first argument name of detach():

Arguments:

name: The object to detach.  Defaults to ‘search()[pos]’.  This can
      be an unquoted name or a character string but _not_ a
      character vector.  If a number is supplied this is taken as
      ‘pos’.

So we need to repeatedly call detach() once per element of pkg. There are a couple of other arguments we need to specify to get this to work. The first is character.only = TRUE, which allows the function to assume that name is a character string - it won't work without it. Second, we also probably want to unload any associated namespace. This can be achieved by setting unload = TRUE. So the solution is, for example:

pkg <- c("package:vegan","package:permute")
lapply(pkg, detach, character.only = TRUE, unload = TRUE)

Here is a full example:

> require(vegan)
Loading required package: vegan
Loading required package: permute
This is vegan 2.0-0
> sessionInfo()
R version 2.13.1 Patched (2011-09-13 r57007)
Platform: x86_64-unknown-linux-gnu (64-bit)

locale:
 [1] LC_CTYPE=en_GB.utf8       LC_NUMERIC=C             
 [3] LC_TIME=en_GB.utf8        LC_COLLATE=en_GB.utf8    
 [5] LC_MONETARY=C             LC_MESSAGES=en_GB.utf8   
 [7] LC_PAPER=en_GB.utf8       LC_NAME=C                
 [9] LC_ADDRESS=C              LC_TELEPHONE=C           
[11] LC_MEASUREMENT=en_GB.utf8 LC_IDENTIFICATION=C      

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods  
[7] base     

other attached packages:
[1] vegan_2.0-0   permute_0.7-0

loaded via a namespace (and not attached):
[1] grid_2.13.1     lattice_0.19-33 tools_2.13.1   
> pkg <- c("package:vegan","package:permute")
> lapply(pkg, detach, character.only = TRUE, unload = TRUE)
[[1]]
NULL

[[2]]
NULL

> sessionInfo()
R version 2.13.1 Patched (2011-09-13 r57007)
Platform: x86_64-unknown-linux-gnu (64-bit)

locale:
 [1] LC_CTYPE=en_GB.utf8       LC_NUMERIC=C             
 [3] LC_TIME=en_GB.utf8        LC_COLLATE=en_GB.utf8    
 [5] LC_MONETARY=C             LC_MESSAGES=en_GB.utf8   
 [7] LC_PAPER=en_GB.utf8       LC_NAME=C                
 [9] LC_ADDRESS=C              LC_TELEPHONE=C           
[11] LC_MEASUREMENT=en_GB.utf8 LC_IDENTIFICATION=C      

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods  
[7] base     

loaded via a namespace (and not attached):
[1] grid_2.13.1     lattice_0.19-33 tools_2.13.1

If you want to turn this into a function, study the code in sessionInfo() to see how it identifies what it labels as "other attached packages:". Combine that bit of code with the idea above in a single function and you are home and dry. I'll leave that bit up to you though.

Answer 4

nothing

It may be worth to add solution made available by Romain François. When loaded the package nothing, which is currently available on GitHub, will unload all of the loaded packages; as in the example that Romain provides:

loadedNamespaces()
[1] "base"      "datasets"  "grDevices" "graphics"  "methods"   "stats"
[7] "utils"

require(nothing, quietly = TRUE)

loadedNamespaces()
[1] "base"

Installation

With use of the devtools package:

devtools::install_github("romainfrancois/nothing")

pacman

An alternative approach uses pacman package available through CRAN:

pacman::p_unload(pacman::p_loaded(), character.only = TRUE)

Answer 5

Building on Gavin's answer but not quite to a full function would be this sequence:

sess.pkgs <- function (package = NULL) 
{   z <- list()
       if (is.null(package)) {
        package <- grep("^package:", search(), value = TRUE)
        keep <- sapply(package, function(x) x == "package:base" || 
            !is.null(attr(as.environment(x), "path")))
        package <- sub("^package:", "", package[keep])
    }
    pkgDesc <- lapply(package, packageDescription)
    if (length(package) == 0) 
        stop("no valid packages were specified")
    basePkgs <- sapply(pkgDesc, function(x) !is.null(x$Priority) && 
        x$Priority == "base")
    z$basePkgs <- package[basePkgs]
    if (any(!basePkgs)) {
        z$otherPkgs <-  package[!basePkgs]
    }
    z
}

lapply(paste("package:",sess.pkgs()$otherPkgs, sep=""), detach, 
                             character.only = TRUE, unload = TRUE)

Answer 6

or if you have RStudio, simply uncheck all the checked boxes in Packages Tab to detach

Answer 7

Most of the times its the plyr vs dplyr issue. Use this in the beginning of the code:

detach("package:plyr", unload=TRUE)

So whenever the script runs, its clears the plyr package

Answer 8

if you're having problems with packages that have similarly named functions conflicting with each other, you can always reference the namespace of the package who's function you DO want.

pkg_name::function_i_want()