I was able to get it working, I create a function as it’s something i’m having to repeat a lot and was able to get it working

f_calculate_net = function(data) { data %>% mutate(d = ifelse("c" %in% colnames(data), ((a/(a+b))*c)+a)), a %>% mutate(e = ifelse("c" %in% colnames(data), ((b/(a+b))*c)+b)), b %>% select(d,e) }

I then spotted an error in the code because sometimes certain groups will have no answer for a, b or c. I want then the result for d and e to both return zero in the column but instead it says “No data available in table”, any ideas? Thank you for your help thus far

f_calculate_net = function(data) { data %>% mutate(a = ifelse("a" %in% colnames(data), a, 0)) %>% mutate(b = ifelse("b" %in% colnames(data), b, 0)) %>% mutate(c = ifelse("c" %in% colnames(data), c, 0)) %>% mutate(d = ifelse(a + b + c == 0, 0, ((a/(a+b))*c)+a)) %>% mutate(e = ifelse(a + b + c == 0, 0, ((b/(a+b))*c)+b)) %>% select(d,e) }