在解决另一个问题时，我遇到了这个问题：

我可以通过以下方法删除所有R对象：

rm(list = ls(all = TRUE))

是否有等效的命令可以在工作会话期间分离已安装的软件包？

> 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 

要求（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 

我尝试过这种方法，尽管即使它不能在全局解决方案中工作：

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

我想要的是全球性的东西：

  rm(list = ls(all = TRUE))

对于对象，期望它不会删除附加的基本包

谢谢;

因此，有人应该简单地回答以下问题。

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

（编辑：6-28-19）在最新版本的R 3.6.0中，请改用。

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

请注意，不需要使用invisible（*），但对于防止NULL回复垂直向R窗口发送垃圾邮件非常有用。

（编辑：9/20/2019）在3.6.1版中

names(sessionInfo()$loadedOnly)先将仅加载的文件转换为显式附加的程序包，然后再分离这些程序包可能会有所帮助。

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

可以尝试通过$ basePkgs卸载基本软件包，也可以尝试使用unloadNamespace(loadedNamespaces())。但是，这些通常充满错误，并且可能破坏基本功能，例如导致sessionInfo()仅返回错误。这通常是由于原始包装设计中缺乏可逆性而发生的。timeDate例如，当前可能无法恢复。

请尝试以下方法：

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()

你近了 请注意?detach关于第一个参数name的说明detach()：

参数：

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’.

因此，我们需要为的detach()每个元素重复调用一次pkg。为了使它起作用，我们需要指定其他几个参数。第一个是character.only = TRUE，它允许函数假定它name是一个字符串-没有它就无法工作。其次，我们可能还希望卸载任何关联的名称空间。可以通过设置来实现unload = TRUE。因此，解决方案是例如：

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

这是一个完整的示例：

> 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

如果要将其转换为函数，请研究其中的代码sessionInfo()以查看其如何标识被标记为“其他附加包：”的内容。将这些代码与上面的想法结合在一个函数中，您将无所事事。不过，我会留给您。

nothing

可能值得添加RomainFrançois提供的解决方案。加载后，该软件包nothing（当前可在GitHub上下载）将卸载所有已加载的软件包。如Romain提供的示例：

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

require(nothing, quietly = TRUE)

loadedNamespaces()
[1] "base"

安装

使用devtools包装：

devtools::install_github("romainfrancois/nothing")

pacman

一种替代方法是使用pacman可通过CRAN获得的软件包：

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

建立在加文的答案之上但并不完全是完整的功能，将是以下顺序：

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)

或者，如果您拥有RStudio，只需取消选中“软件包”选项卡中的所有复选框即可分离

#Detach all  packages
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()

这样可以确保将所有软件包与基本软件包分开

大多数情况下，它是plyrvs dplyr问题。在代码开头使用此代码：

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

因此，每当脚本运行时，它都会清除plyr程序包

如果您在名称相似的函数相互冲突的程序包中遇到问题，则始终可以引用您想要的函数的程序包的名称空间。

pkg_name::function_i_want()

结合各种答案中的一些内容，可以找到我能找到的最强大的解决方案...

packs <- c(names(sessionInfo()$otherPkgs), names(sessionInfo()$loadedOnly))
if(length(packs) > 0){ 
  message('Unloading packages -- if any problems occur, please try this from a fresh R session')
  while(length(packs) > 0){
    newpacks <- c()
    for(packi in 1:length(packs)){
      u=try(unloadNamespace(packs[packi]))
      if(class(u) %in% 'try-error') newpacks <- c(newpacks,packs[packi])
    }
    packs <- newpacks
    Sys.sleep(.1)
  }
}