case_when function to satisfy all exact constraints-CodePudding

I'm working with the case_when() function in R because I'm handling all exceptions in a certain piece of code. My question is rather simple I think, but I'm not sure how to achieve it. With the case_when() function multiple arguments (like in any other statement) can be taken into account. Given the following example;

a <- "aap"

b <- case_when(str_count(a,"a") > 1 ~ 1,
               str_count(a,"a") > 1 & str_count(a,"p") >= 1 ~ 2)

I want to return the value 2, but because the argument of return value 1 is also satisfied, it returns 1 instead of 2. Is there an easy workaround for this? Kind regards

CodePudding user response：

You could invert your conditions. Also, here your second condition is not satisfied (there is one p in aap, not >1). If you type :

b <- case_when(str_count(a,"a") > 1 & str_count(a,"p") >= 1 ~ 2,str_count(a,"a") > 1 ~ 1)

It indeed returns 2.

CodePudding user response：

case_when stops at the first TRUE condition. This is also why an else condition (or "default", if you will) occurs lastly:

case_when(
  a ~ 'a is true and nothing else matters',
  b ~ 'a was not true, but b is, and nothing else matters',
  TRUE ~ 'none of the above was true'
)

Swap the two statements and you should be good.