Initialize an empty tibble with column names and 0 rows

Question

I have a vector of column names called tbl_colnames.

I would like to create a tibble with 0 rows and length(tbl_colnames) columns.

The best way I've found of doing this is...

tbl <- as_tibble(data.frame(matrix(nrow=0,ncol=length(tbl_colnames)))

and then I want to name the columns so...

colnames(tbl) <- tbl_colnames.

My question: Is there a more elegant way of doing this?

something like tbl <- tibble(colnames=tbl_colnames)

Answer 1

my_tibble <- tibble(   var_name_1 = numeric(),   var_name_2 = numeric(),   var_name_3 = numeric(),   var_name_4 = numeric(),   var_name_5 = numeric() ) 

Haven't tried, but I guess it works too if instead of initiating numeric vectors of length 0 you do it with other classes (for example, character()).

This SO question explains how to do it with other R libraries.

According to this tidyverse issue, this won't be a feature for tribbles.

Answer 2

Since you want to combine a list of tibbles. You can just assign NULL to the variable and then bind_rows with other tibbles.

res = NULL for(i in tibbleList)    res = bind_rows(res,i) 

However, a much efficient way to do this is

bind_rows(tibbleList) # combine all tibbles in the list