# A/B Testing for ShoeFly.com (Task 10)

For task 10 in this assignment in Learn R

I’m getting error messages but I don’t know what they mean.

This is my code.

``````# define a_percentage_by_day here:
a_percentage_by_day <- a_clicks_by_day %>%
group_by(day) %>%
mutate(percentage = count/sum(count)) %>%
a_percentage_by_day

# define b_percentage_by_day here:
b_percentage_by_day <- b_clicks_by_day %>%
group_by(day) %>%
mutate(percentage = count/sum(count)) %>%
b_percentage_by_day
``````

I get these error messages, I don’t know what they mean. Would somebody please explain this to me? I thought I was following the instructions exactly.

``````Error in a_percentage_by_day(.): could not find function "a_percentage_by_day"
``````
``````Error in b_percentage_by_day(.): could not find function "b_percentage_by_day"
``````

I am not a subscriber, so I can’t view the instructions/steps.

But why do you have the green pipes? You are defining `a_percentage_by_day` and towards the end, you are trying to pipe the result to `a_percentage_by_day`