Merge dataframes adding date information from filename

Question

I have access from scraped government data, which comes in a less the useful structure. Its 20 dfs that looks like:

Each df is named by the year, eg, X2006.csv is imported in a X2006 dataframe object. They all have a Total row and a total column, which I will deal with later. Now, my question is:

How do I merge these dfs, adding a column with the year information from the dataframe name?

Do not post your data as an image, please learn how to give a [reproducible example](http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example/5963610) — Jaap, Jun 03 '18 at 14:05
[See this Q&A for a possible apporach](https://stackoverflow.com/q/32888757/2204410) — Jaap, Jun 03 '18 at 14:07
Please post code as well in how you import into individual year dfs. — Parfait, Jun 03 '18 at 14:28

DJV · Answer 1 · 2018-06-04T05:42:45.840

1

Instead of using loop you can use do.call:

require(tidyverse)

#Creating sample data set - 10 data.frames
for (i in 1:9){
  assign(paste("x200", i, sep=""),
         data.frame(x = c(1:20)))
  }


#Creating the big data.frame
MyBigDataframe <- do.call(rbind.data.frame, mget(ls(pattern = "x20"))) %>% 
  rownames_to_column("file")

edited Jun 04 '18 at 05:42

answered Jun 03 '18 at 16:32

DJV

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score 0 · Accepted Answer · answered Jun 03 '18 at 15:00

0

startYear <- 1998
endYear <- 2017

myData <- data.frame()

require(plyr)

for (myYear in startYear:endYear){
    df <- get(paste0("X", as.character(myYear)))

    df$Year <- myYear

    myData <- rbind.fill(myData, df)
}

answered Jun 03 '18 at 15:00

Thomas Wire

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Merge dataframes adding date information from filename

2 Answers2