This is very basic (and I suspect this has been asked elsewhere, although not quite here ).
I have a huge number of .rda files each with a single data frame. I would like to do calculations on each data frame and hence need loading them (load()). Had they been .RDS object I would something like:
#My data
x <- data.frame(a=1:3)
y <- data.frame(a=3:6)
#Save as RDS
saveRDS(x, file = "x.rds")
saveRDS(y, file = "y.rds")
files <- c("x.rds", "y.rds")
data <- lapply(files, readRDS)
#Do something with the data in the list "data"
How can I do a similar thing using load since this you cannot assign the data - only the name - to a variable:
x <- data.frame(a=1:3)
> x
a
1 1
2 2
3 3
save(x, file= "x.rda")
x <- load("x.rda")
> x
[1] "x"
If you are certain that all of your files only contain a single object, you could take advantage of the envir argument of load in a wrapper function like this:
load_object <- function(file) {
tmp <- new.env()
load(file = file, envir = tmp)
tmp[[ls(tmp)[1]]]
}
Usage would be as follows:
not_x <- data.frame(xx = 1:5)
save(not_x, file = "~/tmp/x.Rdata")
(x <- load_object("~/tmp/x.Rdata"))
# xx
#1 1
#2 2
#3 3
#4 4
#5 5
all.equal(not_x, x)
#[1] TRUE