将多个.csv文件导入到R中 [英] Importing multiple .csv files into R

问题描述

假设我们有一个包含多个data.csv文件的文件夹，每个文件包含相同数量的变量，但每个变量来自不同的时间。

要同时导入它们而不是单独导入它们？

我的问题是，我有大约2000个数据文件要导入，必须通过使用代码：

  read.delim（file =filename，header = TRUE，sep =\t）
  

效率不高。

方案

类似以下内容应该工作：

  temp = list.files（pattern =*。 csv）
 myfiles = lapply（temp，read.delim）
  

将这些CSV存储在单个目录（您当前的工作目录）中，并且所有这些CSV都具有小写扩展名 .csv 。

更新

快速和脏的解决方案，以获得单独的data.frames（脏，因为我没有打扰清除 .csv 扩展，但这很容易与一些 regex 有关：

  temp = list.files（pattern =*。csv）
 for（i in 1：length（temp））assign（temp [i]，read。 csv（temp [i]））
  

或者， c $ c>，并演示（1）如何清除文件名和（2）显示如何使用 list2env ，您可以尝试以下： p>



  temp = list.files（pattern =*。csv）
 list2env（
 lapply temp，make.names（gsub（*。csv $，，temp））），
 read.csv），envir = .GlobalEnv）
  pre> 
Suppose we have a folder containing multiple data.csv files, each containing the same number of variables but each from from different times.

Is there a way in R to import them all simultaneously rather than having to import them all individually?

My problem is that I have around 2000 data files to import and having to import them individually just by using the code: 
read.delim(file="filename", header=TRUE, sep="\t")
is not very efficient.
解决方案
Something like the following should work:
temp = list.files(pattern="*.csv")
myfiles = lapply(temp, read.delim)
This assumes that you have those CSVs in a single directory--your current working directory--and that all of them have the lower-case extension .csv.

Update

Quick and dirty solution to get separate data.frames ("dirty" because I haven't bothered to clean up the .csv extension, but that's easy enough to do with some regex):
temp = list.files(pattern="*.csv")
for (i in 1:length(temp)) assign(temp[i], read.csv(temp[i]))
Or, without assign, and to demonstrate (1) how the file name can be cleaned up and (2) show how to use list2env, you can try the following:
temp = list.files(pattern="*.csv")
list2env(
  lapply(setNames(temp, make.names(gsub("*.csv$", "", temp))), 
         read.csv), envir = .GlobalEnv)


                        
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