如何reshape 为长格式，删除 NA 单元格

library(tidyverse)

df <- structure(list(zone = c(3, 3, 1, 1, 2, 2, 4, 4), situation = c("Answer", 
"Refusal", "Answer", "Refusal", "Answer", "Refusal", "Answer", 
"Refusal"), `Researcher 1` = c(NA, NA, 10, 7, NA, NA, NA, NA), 
    `Researcher 2` = c(NA, NA, NA, NA, 15, 3, NA, NA), `Researcher 3` = c(4, 
    15, NA, NA, NA, NA, NA, NA), `Researcher 4` = c(NA, NA, NA, 
    NA, NA, NA, 13, 8), `revisit 1` = c(NA, NA, 2, 5, 3, 0, NA, 
    NA), `revisit 2` = c(10, 5, NA, NA, NA, NA, NA, NA), `revisit 3` = c(NA, 
    NA, NA, NA, NA, NA, 4, 4)), class = "data.frame", row.names = c(NA, 
-8L))

df <- df %>% 
  pivot_longer(cols = contains("Researcher"), names_to = "Researchers", values_to = "Result 1") %>% 
  pivot_longer(cols = contains("revisit"), names_to = "revisit", values_to = "Result 2", values_drop_na = TRUE) %>%
  arrange(zone)

# A tibble: 8 × 6
   zone situation Researchers  `Result 1` revisit   `Result 2`
  <dbl> <chr>     <chr>             <dbl> <chr>          <dbl>
1     1 Answer    Researcher 1         10 revisit 1          2
2     1 Refusal   Researcher 1          7 revisit 1          5
3     2 Answer    Researcher 2         15 revisit 1          3
4     2 Refusal   Researcher 2          3 revisit 1          0
5     3 Answer    Researcher 3          4 revisit 2         10
6     3 Refusal   Researcher 3         15 revisit 2          5
7     4 Answer    Researcher 4         13 revisit 3          4
8     4 Refusal   Researcher 4          8 revisit 3          4

然后，您还可以进行更多的清理，以达到以下目的:

mutate(df, situation = as.factor(situation), 
           Researchers = as.numeric(str_remove(Researchers, "Researcher ")),
              revisit = as.numeric(str_remove(revisit, "revisit ")))

# A tibble: 8 × 6
   zone situation Researchers `Result 1` revisit `Result 2`
  <dbl> <fct>           <dbl>      <dbl>   <dbl>      <dbl>
1     1 Answer              1         10       1          2
2     1 Refusal             1          7       1          5
3     2 Answer              2         15       1          3
4     2 Refusal             2          3       1          0
5     3 Answer              3          4       2         10
6     3 Refusal             3         15       2          5
7     4 Answer              4         13       3          4
8     4 Refusal             4          8       3          4