R studio caret package 安装
R安装caret包安装代码install.packages("caret")安装过程中无法打开文件,报错:Warning in install.packages : URL 'http://cran.rstudio.com/bin/macosx/el-capitan/contrib/3.6/caret_6.0-86.tgz': status was 'Failure when receiving data from the peer'Error in download.fi