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rdataframedplyr

dplyr: order columns alphabetically in R

If I have a large DF (hundreds and hundreds) columns with different col_names randomly distributed alphabetically:

df.x <- data.frame(2:11, 1:10, rnorm(10))
colnames(df.x) <- c("ID", "string", "delta")

How would I order all of the data (vertically) by col_name alphabetically?

Essentially, I have hundreds of CSV(sep="|") text files that I need to read their columns into a single df, order those columns alphabetically and then use some other dplyf functions to get a final result. I have all of this figured out except how to order the columns alphabetically. I do not want to sort the columns (up and down) by alphabet, rather, the actual vertical orientation of the col_names and their corresponding data. Analogous to cutting and pasting entire columns of data in Excel.

For example I reviewed this approach but this is the "sort" the rows alphabetically bit, which is not what I'm looking to do.

How to sort a dataframe by column(s)?

Thanks!

Solution

  • Try this

    df %>% select(noquote(order(colnames(df))))

    or just

    df[,order(colnames(df))]

    Update Dec 2021

    New versions of dplyr (>= 1.0.7) work without the noquote:

    df %>% select(order(colnames(df)))