我在这里犯了一些基本错误吗?
install.packages("XML")
Warning in install.packages :
package ‘XML’ is not available (for R version 2.13.0)
Installing package(s) into ‘C:/Program Files/R/R-2.13.0/library’
(as ‘lib’ is unspecified)
Warning in install.packages :
package ‘XML’ is not available (for R version 2.13.0)