我对自己非常熟悉data.table,但在setkeyv功能上遇到了一个我无法解决的奇怪错误.
错误非常简单:
keycols<-c("A", "B")
DT <- data.table(A=1:10, B=91:90)
setkeyv(DT, keycols)
# Error in setkeyv(x, cols, verbose = verbose, physical = physical) :
# 4 arguments passed to .Internal(nchar) which requires 3
作为参考,这是我的sessionInfo():
R version 3.2.0 (2015-04-16)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 7 x64 (build 7601) Service Pack 1
locale:
[1] LC_COLLATE=English_United States.1252 LC_CTYPE=English_United States.1252 LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C LC_TIME=English_United States.1252
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached …