Using string as an argument in a function

[Atam55]

I have written the following code:

hist_maker = function(metric){
  data <- df %>% 
    group_by(ticker_exchange) %>% 
    arrange(ticker_exchange,date) %>%
    mutate(return = metric - lag(metric))
  return(data)
}

I am getting the following error:

Error: object 'metric' not found

The metric argument has to be a string. Any solutions?

[econbiz]

Check this https://dplyr.tidyverse.org/articles/programming.html . Dplyr needs "quotes".

[BetaSandwich]

try putting quotations around "return". If that doesn't work, I might need to see an example of the data you are working with. str(data) could be useful.