Oh okay, sorry. Either way it is more than just a slight improvement :) But yes that would fix everything.
On Wed, Sep 11, 2013 at 5:33 AM, Arunkumar Srinivasan <[email protected] > wrote: > Chris, > It's not filed as a FR, IIRC. It's filed under "Internals". > > Arun > > On Wednesday, September 11, 2013 at 11:31 AM, Chris Neff wrote: > > Yes, dropping names altogether in data.table would fix this, and would be > the cleanest thing overall since as is said in that thread data.table > doesn't really work with rownames in mind anyway. > > Except it is less of a FR now and more of a bad bug because you can get > segfaults from it. > > > On Wed, Sep 11, 2013 at 5:24 AM, Arunkumar Srinivasan < > [email protected]> wrote: > > Most likely, > this<https://r-forge.r-project.org/tracker/index.php?func=detail&aid=4882&group_id=240&atid=5335>, > when fixed, will take care of it? > > Arun > > On Wednesday, September 11, 2013 at 11:17 AM, Chris Neff wrote: > > Indeed, it shows that k1 and k2 both have names of length 2, and both > times the value of names is just the variable names. > > Where the names are getting added is by apply. What the issue with > data.table is that it does not ignore names from short variables. I now > have a small reproducible example I can share: > > d <- data.frame(x=1:5) > > f <- function(x) {data.table(x=x, y=1:10)} > > l <- apply(d, 1, f) > > lapply(l, function(x) lapply(x, names)) # All values of x have a name > > a <- rbindlist(l) # a$x will segfault after this > > > The underlying issue is what data.table and data.frame do with rownames > and recycling. Look at this simple case: > > x <- 1:5 > names(x) <- letters[1:5] > > df <- data.frame(x=x, y=1:10) > #Warning message: > # In data.frame(x = x, y = 1:10) : > # row names were found from a short variable and have been discarded > > lapply(df, names) # no names > > dt <- data.table(x=x, y=1:1) # No warning > > lapply(dt, names) # x has names, and they get recycled. > > > So data.table needs to follow data.frame logic for discarding row names > when they would otherwise be recycled. > > > Bug submitted here: > https://r-forge.r-project.org/tracker/index.php?func=detail&aid=4890&group_id=240&atid=975 > I'm surprised this has never arisen before, it seems like something that > has been around forever. > _______________________________________________ > datatable-help mailing list > [email protected] > https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help > > > > >
_______________________________________________ datatable-help mailing list [email protected] https://lists.r-forge.r-project.org/cgi-bin/mailman/listinfo/datatable-help
