Add (insert) a column between two columns in a data.frame

Question

I have a data frame that has columns a, b, and c. I\'d like to add a new column d between b and c.

I know I could just add d at the end by using cbind but h

Answer 1

df <- data.frame(a=c(1,2), b=c(3,4), c=c(5,6))
df %>%
  mutate(d= a/2) %>%
  select(a, b, d, c)

results

  a b   d c
1 1 3 0.5 5
2 2 4 1.0 6

I suggest to use dplyr::select after dplyr::mutate. It has many helpers to select/de-select subset of columns.

In the context of this question the order by which you select will be reflected in the output data.frame.