R包是R函数的集合,包含代码和样本数据.它们存储在R环境中名为"library"的目录下.默认情况下,R在安装期间安装一组软件包.如果出于某些特定目的需要更多包,则会在以后添加.当我们启动R控制台时,默认情况下只有默认包可用.已经安装的其他软件包必须显式加载以供将要使用它们的R程序使用.
R语言中提供的所有软件包都列在 R Packages.
以下是要执行的命令列表用于检查,验证和使用R包.
获取包含R包的库位置
.libPaths()
当我们执行上述操作时代码,它产生以下结果.它可能会因您的电脑的本地设置而异.
[2]"C:/Program Files/R/R-3.2.2/library"
library()
当我们执行上面的代码时,它会产生以下结果.它可能会因您的电脑的本地设置而异.
Packages in library ‘C:/Program Files/R/R-3.2.2/library’: base The R Base Package boot Bootstrap Functions (Originally by Angelo Canty for S) class Functions for Classification cluster "Finding Groups in Data": Cluster Analysis Extended Rousseeuw et al. codetools Code Analysis Tools for R compiler The R Compiler Package datasets The R Datasets Package foreign Read Data Stored by 'Minitab', 'S', 'SAS', 'SPSS', 'Stata', 'Systat', 'Weka', 'dBase', ... graphics The R Graphics Package grDevices The R Graphics Devices and Support for Colours and Fonts grid The Grid Graphics Package KernSmooth Functions for Kernel Smoothing Supporting Wand & Jones (1995) lattice Trellis Graphics for R MASS Support Functions and Datasets for Venables and Ripley's MASS Matrix Sparse and Dense Matrix Classes and Methods methods Formal Methods and Classes mgcv Mixed GAM Computation Vehicle with GCV/AIC/REML Smoothness Estimation nlme Linear and Nonlinear Mixed Effects Models nnet Feed-Forward Neural Networks and Multinomial Log-Linear Models parallel Support for Parallel computation in R rpart Recursive Partitioning and Regression Trees spatial Functions for Kriging and Point Pattern Analysis splines Regression Spline Functions and Classes stats The R Stats Package stats4 Statistical Functions using S4 Classes survival Survival Analysis tcltk Tcl/Tk Interface tools Tools for Package Development utils The R Utils Package
获取当前加载的所有包R环境
search()
当我们执行上面的代码时,它会产生以下结果.它可能会因您的电脑的本地设置而异.
[1] ".GlobalEnv" "package:stats" "package:graphics" [4] "package:grDevices" "package:utils" "package:datasets" [7] "package:methods" "Autoloads" "package:base"
有两种方法可以添加新的R包.一种是直接从CRAN目录安装,另一种是将软件包下载到本地系统并手动安装.
以下命令直接从CRAN网页获取包,并在R环境中安装包.系统可能会提示您选择最近的镜像.选择适合您所在位置的那个.
install.packages("Package Name") # Install the package named "XML". install.packages("XML")
转到链接 R Packages 下载所需的软件包.将程序包保存为本地系统中适当位置的 .zip 文件.
现在可以运行以下命令在R环境中安装此程序包.
install.packages(file_name_with_path, repos = NULL, type = "source") # Install the package named "XML" install.packages("E:/XML_3.98-1.3.zip", repos = NULL, type = "source")
在可以在代码中使用包之前,必须将它加载到当前的R环境中.您还需要加载先前已安装但在当前环境中不可用的软件包.
使用以下命令加载软件包 :
library("package Name", lib.loc = "path to library") # Load the package named "XML" install.packages("E:/XML_3.98-1.3.zip", repos = NULL, type = "source")