cdt {data.table}R Documentation

data.table exported C routines


Note that this interface is going to be changed in next release. Some of internally used C routines are now exported. This interface should be considered experimental. List of exported C routines and their signatures are provided below in the usage section.


# SEXP subsetDT(SEXP x, SEXP rows, SEXP cols);
# p_dtCsubsetDT = R_GetCCallable("data.table", "CsubsetDT");


For details how to use those see Writing R Extensions manual Linking to native routines in other packages section.


Be aware C routines are likely to have less input validation than their corresponding R interface. For example one should not expect DT[-5L] will be equal to .Call(CsubsetDT, DT, -5L, seq_along(DT)) because translation of i=-5L to seq_len(nrow(DT))[-5L] might be happening on R level. Moreover checks that i argument is in range of 1:nrow(DT), missingness, etc. might be happening on R level too.


[Package data.table version 1.13.3 Index]