csv文件的自动输入和命名

Question

我试图从EPA网站导入许多csv文件。这些csv文件的名称是合理的/一致的。对于如何使用循环来自动输入csv文件并将它们命名为R中的数据文件，有什么建议吗？

现在，我正在手动地在每一行代码中交换月份名称，如下所示：

library(tidyverse)

#Download 2013 data

jan_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_jan2013.csv")%>%
  add_column("month"="jan","year"=2013)
feb_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_feb2013.csv")%>%
  add_column("month"="feb","year"=2013)
mar_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_mar2013.csv")%>%
  add_column("month"="mar","year"=2013)
apr_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_apr2013.csv")%>%
  add_column("month"="apr","year"=2013)
may_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_may2013.csv")%>%
  add_column("month"="may","year"=2013)
jun_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_june2013.csv")%>%
  add_column("month"="jun","year"=2013)
jul_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_july2013.csv")%>%
  add_column("month"="jul","year"=2013)
aug_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_aug2013.csv")%>%
  add_column("month"="aug","year"=2013)
sep_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_sept2013.csv")%>%
  add_column("month"="sep","year"=2013)
oct_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_oct2013.csv")%>%
  add_column("month"="oct","year"=2013)
nov_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_nov2013.csv")%>%
  add_column("month"="nov","year"=2013)
dec_13<-read.csv("https://www.epa.gov/sites/default/files/2017-10/rindata_dec2013.csv")%>%
  add_column("month"="dec","year"=2013)

我想设置一些东西，在这里导入所有12个月，适当地修改添加的列，并按月份对结果的df进行适当的命名。

谢谢你的帮助！

Answer 1

使用月份向量和字符串连接读取所有csvs，然后设置它们的名称、帧、添加一个年份列和取消嵌套：

months <- c("jan", "feb", "mar", "apr", "may", "june", "july", "aug", "sept", "oct", "nov", "dec")

dfs <- lapply(months, function(x) read.csv(paste0("https://www.epa.gov/sites/default/files/2017-10/rindata_", x, "2013.csv"))) %>%
  setNames(months) %>%
  enframe(name = "month") %>%
  add_column(year = 2013) %>%
  unnest(value)

如果这有用的话请告诉我！