Question

我有一个包含

的foo.R文件

library("ggplot2")
cat("Its working")

我正在尝试使用Rscript命令Rscript --default-packages=ggplot2 foo.R通过命令行运行foo.r并且它给了我以下错误：

1: In library(package, lib.loc = lib.loc, character.only = TRUE, logical.return = TRUE,  :
  there is no package called ‘ggplot2’
2: package ‘ggplot2’ in options("defaultPackages") was not found 
Error in library("ggplot2") : there is no package called ‘ggplot2’
Execution halted

有关如何在运行时加载包的任何帮助＆＃34; Rscript＆＃34;非常感谢。

Answer 1

对于将来的引用，您可以使用函数require而不是library来避免此错误：require只返回FALSE并在未安装软件包时引发警告而不是抛出错误错误。因此，您可以按如下方式进行构造：

if(!require(ggplot2)){install.packages("ggplot2")}

它的作用是尝试加载软件包，如果没有安装，则安装它。

Answer 2

或者你可以使用它，

# --------- Helper Functions ------------ #
# Ref: https://gist.github.com/smithdanielle/9913897
# check.packages 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.
check.packages <- function (pkg) {
  print("Installing required packages, please wait...")
  new.pkg <- pkg[!(pkg %in% installed.packages()[, "Package"])]
  if (length(new.pkg)) {
    install.packages(new.pkg, dependencies = TRUE)
  }
  sapply(pkg, library, character.only = TRUE)
}

# Usage example
# packages<-c("ggplot2", "afex", "ez", "Hmisc", "pander", "plyr")
# check.packages(packages)

check.packages("tidyverse")

在命令行中运行Rscript并加载包

2 个答案: