Same Column Names in flextable in R

Question

I am trying to create a 'flexable' object from the R package "flextable". I need to put same column names in more than one columns. When I am putting them in the the "col_key" option in the function "flextable" I am getting the error of "duplicated col_keys". Is there a way to solve this problem?

a<-c(1:8)
b<-c(1:8)
c<-c(2:9)
d<-c(2:9)
A<-flextable(A,col_keys=c("a","b","a","b"))

This is the example code for which I am getting the error.

Frampton

Welcome! You're more likely to get answers if you edit your question to include a reproducible example of your problem - it is easier for others to help if they can see what your data and code looks like. See How to make a great R reproducible example – Raimundo

Thank you for the comment. I have added an example code. – Frampton

Answer 1

As it stands now, flextable does not allow duplicate column keys. However, you can achieve the same result by adding a row of "headers," or a row of column labels, to the top of your table. These headers can contain duplicate values.

You do this with the "add_header_row" function.

Here is a base example using the iris data set.

ft <- add_header_row(
  ft, 
  values = c("", "length", "width", "length", "width"), 
  top = FALSE 
)
ft <- theme_box(ft)

https://davidgohel.github.io/flextable/articles/layout.html

Wolter

Although your answer could be 100% correct, it might also become 100% useless if that link is moved, changed, merged into another one or the main site just disappears... :-( Therefore, please edit your answer, and copy the relevant steps from the link into your answer, thereby guaranteeing your answer for 100% of the lifetime of this site! ;-) You can always leave the link in at the bottom of your answer as a source for your material... – Connors

Answer 2

I found a work around by adding the character \r to the column names to create unique column names :

library(flextable)
A <- matrix(rnorm(8), nrow = 2, ncol = 4)
A <- as.data.frame(A)
col_Names <- c("a","b","a","b")
nb_Col_Names <- length(col_Names)

for(i in 1 : nb_Col_Names)
{
  col_Names[i] <- paste0(col_Names[i], paste0(rep("\r", i), collapse = ""), collapse = "")
}

colnames(A) <- col_Names
tbl_A <- flextable(A)

Breadboard

I solved similar problem by adding space character at the end of one of the column. – Selfcentered

Answer 3

Currently, using set_header_labels:

library(flextable)
a<-c(1:8)
b<-c(1:8)
c<-c(2:9)
d<-c(2:9)
A <- data.frame(a,b,c,d)
flextable(A) |> set_header_labels(`a` = "a", `b` = "b", `c` = "a", `d` = "b")

Hernandez

Answer 4

In my case, I added the header and delete the previouse one.

library(flextable)
a<-c(1:8)
b<-c(1:8)
c<-c(2:9)
d<-c(2:9)
A<-data.frame(a,b,c,d)
A %>% flextable() %>% add_header_row(values=c("a","b","a","b"), top=FALSE) %>% delete_rows(i=1,part="header")

Dashed