How to ignore ranking if the data conatins NaN or Inf in R?

Question

I have a dataframe that contains NaN and Inf. I want to rank the data based on a variable (Q). So, I am using

rank(df$Q, ties.method= "first")

#> [1]  3  5  6  4  2  9  7 10  8  1

As you can see that even NaN and Inf are also ranked.

So, I want to ignore the ranking if the data contains NaN and Inf. I am using the following code:

#Checking if Q is valid
if((df$Q %in% "NaN") || (df$Q %in% "Inf")){
  RankingQ <- rep("-", nrow(df))
}else{
  RankingQ <- rank(df$Q, ties.method= "first") 
}

It returns the following error:

Error in (df$Q %in% "NaN") || (df$Q %in% "Inf") : 'length = 10' in coercion to 'logical(1)'

It used to work before with a warning (R ver. 4.2.0). But in R version 4.3.0, it returns an error

Calling && or || with LHS or (if evaluated) RHS of length greater than one is now always an error, with a report of the form

'length = 4' in coercion to 'logical(1)'

My input is

df <- structure(list(Alternatives = 1:10, Q = c(0.375, 0.5, 0.5, 0.469, 
0.219, NaN, Inf, NaN, Inf, 0.153)), class = "data.frame", row.names = c(NA, 
-10L))

My desired output is

Alternatives    Q   Rank
1             0.375 3
2             0.500 5
3             0.500 6
4             0.469 4
5             0.219 2
6             NaN   NA
7             Inf   NA
8             NaN   NA
9             Inf   NA
10            0.153 1

How can I solve this problem?

Answer 1

Using tidyverse:

df %>% 
  mutate(Rank = ifelse(is.na(Q) | is.infinite(Q), NA, rank(Q, ties.method = "first")))

   Alternatives     Q Rank
1             1 0.375    3
2             2 0.500    5
3             3 0.500    6
4             4 0.469    4
5             5 0.219    2
6             6   NaN   NA
7             7   Inf   NA
8             8   NaN   NA
9             9   Inf   NA
10           10 0.153    1

Using base R:

df$Rank <- ifelse(is.na(df$Q) | is.infinite(df$Q), NA, rank(df$Q, ties.method = "first"))