How to rename column of single column DataFrame in R

I have a list of single column dataframes. The dataframes have all the same rows and I would like to change the value of the single column to the name of the dataframe (Index in list).

So I wrote a function:

change_colname <- function(df_list) { name_vector <- names(df_list) for (i in length(name_vector)) { working_name = toString(name_vector[i]) working_df = df_list[i] colnames(working_df) <- working_name } } 

This returns:

Error in `colnames<-`(`*tmp*`, value = working_name) : attempt to set 'colnames' on an object with less than two dimensions 

Well, then I read about single column dataframes, that they are a problem in R and thought I could transpose the dataframe.

df_list <- lapply(df_list, function(x){t(x)}) df_list <- lapply(df_list, data.frame) 

Changed the function accordingly:

change_rowname <- function(df_list) { name_vector <- names(df_list) for (i in length(name_vector)) { working_name = toString(name_vector[i]) working_df = df_list[i] rownames(working_df) <- working_name } } 

This returns:

Error in `rownames<-`(`*tmp*`, value = working_name) : attempt to set 'rownames' on an object with no dimensions 

However something must be wrong in my function, since when I try in the console:

dim(df_list$df) 

It returns:

[1] 96 1 

and for the transposed:

[1] 1 96 

Hence written in the function:

print(dim(working_df)) 

it returns:

NULL 

but:

print(working_df) 

returns the entire dataframe.

Does anybody know what is the problem here?

Thanks in advance and best regards Lukas