Hello,
I am pretty new to R…
I created a new column var (all_bis) using mutate () to add to existing ones to my database (roma_obs) . The new var is the difference between two vars (see code below). I could not use the rename () function as I did not really understand its use (perhaps it is needed in case I want to replace a var rather than adding a new one?).

I need to save the new column var (all_bis) to either the existing (roma_obs) or a new database (roma_obs_bis) in excel (would be better the first solution). However I have problems with your code lines at this step. I used the write_xls () for excel files…without success (Error in is.data.frame(x) : object “roma_obs_bis” not found).

Do you have suggestions how to overwrite existing db in Excel with the new one including the new var??

roma_obs_bis %
mutate(all_bis = roma_obs$all – roma_obs$all_0_30) %>%
rename(all = all_bis) # NOT SURE

write_xlsx(roma_obs_bis, path = tempfile(fileext = ‘…\roma_obs_bis.xlsx’)) # NOT SURE

Thank you very much for your help

Try the function arrange() [in dplyr package].

Read more at: https://www.datanovia.com/en/lessons/reorder-data-frame-rows-in-r/

How can i sort a column after piping?

For example :
Code : { aggregate(df[, c(3)], list(Region = df$Region), mean) %>%
left_join(count(df, “Region”)) }

I get :
Region x freq
1 Australia and New Zealand 7.298000 2
2 Central and Eastern Europe 5.469448 29
3 Eastern Asia 5.672000 6
4 Latin America and Caribbean 5.950136 22
5 Middle East and Northern Africa 5.294158 19
6 North America 7.107000 2
…
> now i want to sort x descending .. i tried :
{ “%>%
sort( x, decreasing = TRUE) }
and get error : Error in do.call(“order”, c(z, list(na.last = na.last, decreasing = decreasing, :
object ‘x’ not found

How can i sort the output of piping ?

Thnaks !! :]

Normally, you just need to load the tidyverse package.

The function `%>%` is available in the magrittr package, which is automatically loaded by tidyverse.

Please, try this:

library(tidyverse)
library(magrittr)

Many thanks!

I realize I was struggling to understand the pipe concept.

It’s not virtual, you need to create a new R object to hold the modified data frame; then, you can save or manipulate the data again.

For example:

library(tidyverse)
my_modified_data <- iris %>%
  mutate(sep.lw = Sepal.Length*Sepal.Width) %>%
  rename(Sepal.Len.Width = sep.lw)

write_csv(my_modified_data, "my_modified_data.csv")

How can I force the variable to persist?