全角数字列を半角数字列へ

encoding 依存かな。Mac なら以下も。

> x <- "２００８"
> paste(as.character(as.integer(sapply(unlist(strsplit(x, "")), charToRaw)[3,])-9*16), collapse="")
[1] "2008"

> paste(as.character(as.integer(sapply(unlist(strsplit(x, "")), charToRaw)[3,])%%16), collapse="")
[1] "2008"

 

Windows ならば

paste(as.character(as.integer(sapply(unlist(strsplit(x, "")), charToRaw)[2,])-79), collapse="")