This is calling for some "tricky R", but this time it's beyond my fantasy :-) I need to save() an object whose name is in the variable var. I tried:
save(get(var), file = ofn)
# Error in save(get(var), file = ofn) : object ‘get(var)’ not found
save(eval(parse(text = var)), file = ofn)
# Error in save(eval(parse(text = var)), file = ofn) :
# object ‘eval(parse(text = var))’ not found
both of which fail, unfortunatelly. How would you solve this?
Use the list argument. This saves x in the file x.RData. (The list argument can specify a vector of names if you need to save more than one at a time.)
x <- 3
name.of.x <- "x"
save(list = name.of.x, file = "x.RData")
# loading x.RData to check that it worked
rm(x)
load("x.RData")
x
## [1] 3
Regarding the first attempt in the question which attempts to use get we need to specify the name rather than its value so that attempt could use do.call converting the character name to a name class object.
do.call("save", list(as.name(name.of.x), file = "x.RData"))
Regarding the second attempt in the question which uses eval, to do that write out the save, substitute in its name as a name class object and then evaluate it.
eval(substitute(save(Name, file = "x.RData"), list(Name = as.name(name.of.x))))
?save but I totally missed this argument! Thanks!If it's just one object, you can use saveRDS:
a<-1:4
var<-"a"
saveRDS(get(var),file="test.R")
readRDS(file="test.R")
[1] 1 2 3 4
.Rdata. I prefer to stay with .Rdata.