I'm diverting to R-devel, where this is really more appropriate. >>>>> "RichOK" == Richard A O'Keefe <[EMAIL PROTECTED]> >>>>> on Fri, 10 Dec 2004 14:37:16 +1300 (NZDT) writes:
RichOK> In this discussion of seq(), can anyone explain to RichOK> me _why_ seq(to=n) and seq(length=3) have different RichOK> types? well, the explantion isn't hard: look at seq.default :-) RichOK> In fact, it's worse than that (R2.0.1): >> storage.mode(seq(length=0)) RichOK> [1] "integer" >> storage.mode(seq(length=1)) RichOK> [1] "double" { str(.) is shorter than storage.mode(.) } RichOK> If you want to pass seq(length=n) to a .C or RichOK> .Fortran call, it's not helpful that you can't tell RichOK> what the type is until you know n! It would be nice RichOK> if seq(length=n) always returned the same type. I RichOK> use seq(length=n) often instead of 1:n because I'd RichOK> like my code to work when n == 0; it would make life RichOK> simpler if seq(length=n) and 1:n were the same type. now if that really makes your *life* simpler, what does that tell us about your life ;-) :-) But yes, you are right. All should return integer I think. BTW --- since this is now on R-devel where we discuss R development: In the future, we really might want to have a new type, some "long integer" or "index" which would be used both in R and C's R-API for indexing into large objects where 32-bit integers overflow. I assume, we will keep the R "integer" == C "int" == 32-bit int forever, but need something with more bits rather sooner than later. But in any, case by then, some things might have to change in R (and C's R-API) storage type of indexing. RichOK> Can anyone explain to me why the arguments of seq.default are RichOK> "from", "to", "by", "length.out", "along.with" RichOK> ^^^^ ^^^^^ RichOK> when the help page for seq documents them as RichOK> "from", "to", "by", "length", and "along"? Well I can explain why this wasn't caught by R's builtin QA (quality assurance) checks: The base/man/seq.Rd page uses both \synopsis{} and \usage{} which allows to put things on the help page that are not checked to coincide with the code... I'm about to fix this (documentation, not code). Martin ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-devel