R Creating a list of multiple dataframes

Asked Oct 30 '17 at 08:16

Active Oct 30 '17 at 08:26

Viewed 70 times

I need to extract column 2 from a list of multiple dataframe. I have 18 files and I was able to do it by reading each file separately.

df1 <- read.table("name.XLS", header = FALSE)
df2 <- read.table("name.XLS", header = FALSE)
df3 <- read.table("name.XLS", header = FALSE)
df4 <- read.table("name.XLS", header = FALSE)

data_list = list(df1, df2,df3,df4)
# extract column named V2
res = lapply(data_list, '[[', 2)
# convert to character
res = lapply(res, as.character)

I modified the code to read all files in the directory

folder <- "temp"  
file_list <- list.files(path=folder, pattern="*.XLS") 

for (i in 1:length(file_list)){
  assign(file_list[i], 
         read.csv(paste(folder, file_list[i], sep="/"))
  )}

I need to create an equivalent list to data_list that reads a list of multiple dataframe to extract column V2 from each dataframe in the list

EDIT

I tried the following code and it worked just fine

my_data <- lapply(file_list, read.table)

You can find more about lists here

edited Oct 30 '17 at 08:26

asked Oct 30 '17 at 08:16

user91

Do you need all data.frame or only column 2? – pogibas Oct 30 '17 at 08:21
I needed dataframes with all variables and columns. I found the answer and I have modified the question. Thank you! – user91 Oct 30 '17 at 08:27
Try `data_list – lukeA Oct 30 '17 at 08:27
@lukeA worked, but wasn't able to extract V2. I changed it to read.table but still the same – user91 Oct 30 '17 at 08:59

R Creating a list of multiple dataframes

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