Question

我有一组csv文件，它们在所有文件中包含相同格式的数据。格式如下

CA.csv  -- 

row:1- jones            
row:2- May          
row:3-
row:4- Date_transaction cards_hold  status  amount
row:5- 5/25/2018 3:15      2            Active  233
row:6- 5/25/2018 3:30      2            Active  4534

 NY.csv  --
row:1- gary         
row:2- May          
row:3-
row:4- Date_transaction cards_hold  status  amount
row:5- 5/25/2018 5:00      2            Active  565
row:6- 5/25/2018 6:30      2            Active  533

以上格式会针对所有其他csv文件重复

o/p (i.e name is in first row in csv file should read and create as value in "name" column)
Date_transaction    cards_hold  status  amount  name
5/25/2018 3:15     2            Active  233     jones
5/25/2018 3:30     2            Active  4534    jones
5/25/2018 5:00     2            Active  565     gary
5/25/2018 6:30     2            Active  533     gary

我尝试使用以下代码。

 files <- dir("RawData", recursive=TRUE, full.names=TRUE, pattern="\\.csv$")
   raw = rbindlist(lapply(files, fread))

Answer 1

希望这有帮助！

setwd("directory_path_of_your_csv_files/")
file_lst <- list.files(".")

read_all_csv <- function(f_name){
  csv_data <- read.csv(f_name, header=T, stringsAsFactors=F, skip=3)
  name <- read.csv(f_name, header=F, nrows=1)$V1
  csv_data$name <- rep(name, nrow(csv_data))
  csv_data
}

df <- Reduce(rbind, lapply(file_lst, function(x) read_all_csv(x)))

读取csv并在新列中创建行-1作为值

1 个答案: