我怎么能一次加载一堆包，而不需要一遍又一遍地键入要求命令?我尝试了三种方法，都失败了。
基本上，我想为一个函数提供一个包名向量，该函数将加载它们。
x<-c("plyr", "psych", "tm")
require(x)
lapply(x, require)
do.call("require", x)
当前回答
对于那些想要同时安装和加载包的人来说，我从这个链接中遇到了这个函数
# ipak function: install and load multiple R packages.
# check to see if packages are installed. Install them if they are not, then load them into the R session.
ipak <- function(pkg){
new.pkg <- pkg[!(pkg %in% installed.packages()[, "Package"])]
if (length(new.pkg))
install.packages(new.pkg, dependencies = TRUE)
sapply(pkg, require, character.only = TRUE)
}
# usage
packages <- c("ggplot2", "plyr", "reshape2", "RColorBrewer", "scales", "grid")
ipak(packages)
其他回答
另一个选项来自软件包easypackages(需要安装)。你可以用最直观的方式加载包:
library("easypackages")
libraries("plyr", "psych", "tm")
该包还包括一个安装几个包的函数:
packages("plyr", "psych", "tm")
参考这里。
你所提议的函数的几种排列是可行的——但前提是你指定了字符。唯一的论点为真。简单的例子:
lapply(x, require, character.only = TRUE)
对于那些想要同时安装和加载包的人来说，我从这个链接中遇到了这个函数
# ipak function: install and load multiple R packages.
# check to see if packages are installed. Install them if they are not, then load them into the R session.
ipak <- function(pkg){
new.pkg <- pkg[!(pkg %in% installed.packages()[, "Package"])]
if (length(new.pkg))
install.packages(new.pkg, dependencies = TRUE)
sapply(pkg, require, character.only = TRUE)
}
# usage
packages <- c("ggplot2", "plyr", "reshape2", "RColorBrewer", "scales", "grid")
ipak(packages)
我使用以下函数:
mrip <- function(..., install = TRUE){
reqFun <- function(pack) {
if(!suppressWarnings(suppressMessages(require(pack, character.only = TRUE)))) {
message(paste0("unable to load package ", pack,
": attempting to download & then load"))
install.packages(pack)
require(pack, character.only = TRUE)
}
}
lapply(..., reqFun)
}
这将尝试加载，如果失败，则安装，然后尝试再次加载。
我维护的CRAN包pacman(与Dason Kurkiewicz合著)可以实现这一点:
所以用户可以这样做:
## install.packages("pacman")
pacman::p_load(dplyr, psych, tm)
如果包丢失，p_load将从CRAN或Bioconductor下载它。
