Change data type from dbl to int for one column only

Question

Assignment Task: Need help to change the data type to integer format for the n column only.

Here is the code:

pizza %>%
  select(day,driver,free_wine)%>%
  group_by(day,driver)%>%
  summarise(n=sum(free_wine,na.rm=TRUE),.groups = 'drop')%>%
  arrange(desc(n))%>%
  head(1)%>%
  as.integer(n)

Note: current data format is dbl for n column - I can only use tidyverse library and prefer to use function as.integer().

Code is not working - giving below error

Warning in pizza %>% select(day, driver, free_wine) %>% group_by(day, driver) %>%  :
  
NAs introduced by coercion

And gives this output:

[1] NA NA 20

The expected output should be in the below format

Day       Driver  n
<chr>     <chr>   <int>
Thursday  Rick    20

Answer 1

Your code as written passes the entire dataframe to as.integer(). To instead apply it to just one column, you can add it to your summarise() call:

pizza %>%
  select(day,driver,free_wine)%>%
  group_by(day,driver)%>%
  summarise(n=as.integer(sum(free_wine,na.rm=TRUE)),.groups = 'drop')%>%
  arrange(desc(n))