r - Dropping columns out of loading files into a list -


this question has answer here:

i'm working huge data files (several hundred mbs) , need efficient possible. i'm using lapply function load files list, due nature of file origin there couple columns don't need. 

dfs <- list.files(pattern="*.txt") dfss <- lapply(dfs,read.table)

i use drop=c("id","num") command read.table:

file <- read.table(drop=c("id","num"))

but won't work here. suggestions?

what :

dfss <- lapply(dfs,read.table,drop=c("id","num"))

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