[R] How to aggregate values in corresponding dataframes

[Rui Barradas]

Hello,

Maybe something like this?
Note that you *never* need to set header = FALSE, it already is the 
default of read.table. You would have to with read.csv.


old_dir <- setwd("~/directory")
f1990 <- list.files(pattern = "^199.*\\.txt$")
r1990 <- lapply(f1990, read.table)
setwd(old_dir)


Hope this helps,

Rui Barradas


Às 08:30 de 25/03/2019, lily li escreveu:
> Hi R users,
> 
> I have multiple dataframes in a directory, and with the same postfix
> ".txt". Each dataframe is a gridded file with just values, but each value
> represents one grid cell. There are many years, and each year has 12
> months, so there are many such files. For each year, I want to read the
> corresponding year's files and add the values of the dataframes, but I
> don't know how to do that. For example, the file names are
> 1990_file01.txt
> 1990_file02.txt
> ...
> 1990_file12.txt
> 1991_file01.txt
> ...
> 1991_file12.txt
> ...
> 
> And my code is like this:
> f1990 = list.files("~/directory", pattern = "^1990(.*).txt$")
> for(i in 1:length(f1990)){
> r1990 = read.table(paste('~/directory',f1990[i],sep='/'),head=F)
> }
> 
> Could you provide some help on this? Thanks very much.
> 
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> 
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