add non permanent vectors to data frame using rbind - r

Question

i've non permanent vectors that i like to merge them to one data frame,
im using the following loop to create those vectors
for (i in campagin_id){
h <- basicHeaderGatherer()
doc <- getURI(paste0(automations_url,
"/",i,
"?apikey=",accessToken,
"&count=",pagination), headerfunction = h$update)
assign(paste0('web_id',i),c(i,as.integer(substring(h$value()[as.integer(grep(SearchTerm, h$value()))],
as.integer(regexpr(SearchTerm,h$value()[as.integer(grep(SearchTerm, h$value()))]))+nchar(SearchTerm)-1,as.integer(regexpr(SearchTerm,h$value()[as.integer(grep(SearchTerm, h$value()))]))+nchar(SearchTerm)+StringLength-2))))
}
i received list of vectors and i like to marge them with rbind something like that
rbind(web_id0f09cc8ddd,web_id18a71f70a8)
the issue is that i don't not how many vectors i will get but i knows only the beginning of the vector name, so i'm trying to run the following loop
for (i in campagin_id) {
web_id <- do.call("rbind",list(paste0('web_id',i)))
}
but it insert only one vector to the data frame
the campaign_id contains all the i values i need in specific time
Thanks

Answer 1

do.call is the right idea, but rbind is a slow operation. You should add your vectors to a list one-at-a-time, and then do a single rbind at the end, something like this (untested, obviously, as the example isn't reproducible, but it should give you the idea):
result_list = list(length = length(campagin_id))
for (i in campagin_id) {
h <- basicHeaderGatherer()
doc <- getURI(
paste0(
automations_url,
"/",
i,
"?apikey=",
accessToken,
"&count=",
pagination
),
headerfunction = h$update
)
result_list[[i]] = c(i, as.integer(
substring(
h$value()[as.integer(grep(SearchTerm, h$value()))],
as.integer(regexpr(SearchTerm, h$value()[as.integer(grep(SearchTerm, h$value()))])) +
nchar(SearchTerm) - 1,
as.integer(regexpr(SearchTerm, h$value()[as.integer(grep(SearchTerm, h$value()))])) +
nchar(SearchTerm) + StringLength - 2
)
))
}
results = do.call(rbind, result_list)