On Apr 1, 2013, at 1:10 PM, Terry Therneau wrote: > Assume a C program invoked by .Call, that returns a list. > > Near the top of the program we allocate space for all the list elements. (It > is my habit to use "xyz2" for the name of the R object and "xyz" for the > pointer to its contents.) > > PROTECT(means2 = allocVector(REALSXP, nvar)); > means = REAL(means2); > PROTECT(u2 = allocVector(REALSXP, nvar)); > u = REAL(u2); > PROTECT(loglik2 = allocVector(REALSXP, 2)); > loglik = REAL(loglik2); > > PROTECT(rlist = mknamed(VECSXP, outnames)); > > Can I assign the individual elements into rlist using SET_VECTOR_ELT at this > point, or do I need to wait until the end of the program, after I've filled > in means[i], u[i], etc.? I likely depends on whether I'm assigning a pointer > or a copy. >
You're assigning a pointer, so it doesn't matter. FWIW, you can avoid all the PROTECTion mess if you alloc+assign, e.g. SEXP rlist = PROTECT(mknamed(VECSXP, outnames)); SEXP means = SET_VECTOR_ELT(rlist, 0, allocVector(REALSXP, nvar)); ... since you only need to protect the parent object. Cheers, Simon ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
