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I want to sort a data frame by a variable number of columns. For example, with the data frame below, I would like to sort by column "x" then by column "y":

df <- data.frame(x = c("A", "D", "A", "C", "D"), y = c(8, 3, 9, 9, 8),
      z = c(1, 1, 1, 2, 1))

I cannot specify columns like:

library(dplyr)
arrange(df,x,y)

because my code must be able to order data frame by a variable number of columns (for this data frame: 1, 2 or 3 columns).

I tried the following:

columnsOrder = c("x","y")
arrange(df,columnsOrder)

But it doesn't work.

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  • Or maybe arrange(df, !!as.symbol(columnsOrder)), not sure how it works just copied from stackoverflow.com/questions/49015759/… Commented Oct 3, 2018 at 7:53
  • 1
    Question: Are you limited for some reason to only using the arrange function to sort your data frame? Commented Oct 3, 2018 at 7:57
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    @TimBiegeleisen from what I understand, OP wants to use a vector containing variables to be used for the sorting without having to specify the variables directly in the call to arrange, so question a bit more specific than just order/sort, but maybe the answer is still somewhere in the Q&A Commented Oct 3, 2018 at 7:57
  • Thanks @RonakShah arrange(df, !!as.symbol(columnsOrder)) works. Commented Oct 3, 2018 at 9:37
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    @Cath You perfectly understand the problem. Thanks, your solution is more elegant or simple. Commented Oct 3, 2018 at 9:48

1 Answer 1

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If you want to "reach" the real columns, you can either use function arrange_ (which is deprecated now...) instead of arrange, with parameter .dots to pass your vector of variable names:

arrange_(df, .dots=columnsOrder)
#  x y z
#1 A 8 1
#2 A 9 1
#3 C 9 2
#4 D 3 1
#5 D 8 1

Or you can do it with rlang::syms and quasiquotation to create names from your strings vector:

df %>% arrange(!!! rlang::syms(columnsOrder))
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2 Comments

Unfortunately, I tested it with another data frame: df <- data.frame(x = c("A", "D", "A", "C", "D"), y = c(8, 8, 9, 9, 3), z = c(1, 1, 1, 2, 1)) and it was just sorted by first column.
Hi @Chris, indeed get wasn't going past the first variable, I edited my answer, it should work now

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