The gsubfn package can do that. library(gsubfn)
# swap a and b without explicitly creating a temporary a <- 1; b <- 2 list[a,b] <- list(b,a) # get eigenvectors and eigenvalues list[eval, evec] <- eigen(cbind(1,1:3,3:1)) # get today's month, day, year require(chron) list[Month, Day, Year] <- month.day.year(unclass(Sys.Date())) # get first two components of linear model ignoring rest list[Coef, Resid] <- lm(rnorm(10) ~ seq(10)) # assign Green and Blue (but not Red) components list[,Green,Blue] <- col2rgb("aquamarine") # Assign QR and QRaux but not other components list[QR,,QRaux] <- qr(c(1,1:3,3:1)) On Sat, Mar 11, 2023 at 7:47 AM Sebastian Martin Krantz <sebastian.kra...@graduateinstitute.ch> wrote: > > Dear R Core, > > working on my dynamic factor modelling package, which requires several > subroutines to create and update several system matrices, I come back to > the issue of being annoyed by R not supporting multiple assignment out of > the box like Matlab, Python and julia. e.g. something like > > A, C, Q, R = init_matrices(X, Y, Z) > > would be a great addition to the language. I know there are several > workarounds such as the %<-% operator in the zeallot package or my own %=% > operator in collapse, but these don't work well for package development as > R CMD Check warns about missing global bindings for the created variables, > e.g. I would have to use > > A <- C <- Q <- R <- NULL > .c(A, C, Q, R) %=% init_matrices(X, Y, Z) > > in a package, which is simply annoying. Of course the standard way of > > init <- init_matrices(X, Y, Z) > A <- init$A; C <- init$C; Q <- init$Q; R <- init$R > rm(init) > > is also super cumbersome compared to Python or Julia. Another reason is of > course performance, even my %=% operator written in C has a non-negligible > performance cost for very tight loops, compared to a solution at the > interpretor level or in a primitive function such as `=`. > > So my conclusion at this point is that it is just significantly easier to > implement such codes in Julia, in addition to the greater performance it > offers. There are obvious reasons why I am still coding in R and C, thanks > to the robust API and great ecosystem of packages, but adding this could be > a presumably low-hanging fruit to make my life a bit easier. Several issues > for this have been filed on Stackoverflow, the most popular one ( > https://stackoverflow.com/questions/7519790/assign-multiple-new-variables-on-lhs-in-a-single-line) > has been viewed 77 thousand times. > > But maybe this has already been discussed here and already decided against. > In that case, a way to browse R-devel archives to find out would be nice. > > Best regards, > > Sebastian > > [[alternative HTML version deleted]] > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel -- Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.com ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel