CODEWITHSUNDEEP
rdata.table
bziggy
bziggy

Reputation: 463

R: data.table Subsetting multiple data sets at the same time

I am currently using data.table in R and am attempting to subset a list of several data tables down to one specific variable called "name". I have tried using lapply to do so, but haven't been successful. Is there something wrong with my code?

Here's what I've tried:

   data_tables<-c("one", "two", "three", "four", "five")
   lapply(mget(data_tables),function(x)x[, c("name")])

Upvotes: 0

Views: 367

Answers (1)

akrun
akrun

Reputation: 887168

We can use .(

library(data.table)
lapply(mget(data_tables),function(x)x[, .(name)])

Or specify the column/columns in .SDcols and subset the .SD

lapply(mget(data_tables),function(x)x[, .SD, .SDcols = 'name'])

Or if we want to extract as a vector, use [[

lapply(mget(data_tables),function(x) x[["name"]])

Upvotes: 3

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