Need to find which players played in which year(s) using R

Question

I have baseball data and need to find which players --

1. played in 1945 but not 1946.
2. did not play in either year.
3. played in both 1945 and 1946.

For #1, the desired output would be --

player  
Albert
Barnes

For #2, the desired output would be --

player
Andrews
David

For #3, the desired output would be --

player
Baker
Frank

I would prefer a dplyr solution but am open to others. I could not find a solution in stackoverflow that matched my situation. If one exists, I would appreciate it if you could share its link.

Input sample

Dput data sample

structure(list(player = c("Albert", "Andrews", "Baker", "Charles", 
"Baker", "David", "Frank", "Barnes", "Ross", "Frank", "Frank"
), year = c(1945, 1944, 1946, 1946, 1945, 1947, 1945, 1945, 1946, 
1946, 1947)), class = "data.frame", row.names = c(NA, -11L))

Answer 1

This should do it:

library(dplyr)
#> 
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union
dat <- structure(list(player = c("Albert", "Andrews", "Baker", "Charles", 
                                 "Baker", "David", "Frank", "Barnes", "Ross", "Frank", "Frank"
), year = c(1945, 1944, 1946, 1946, 1945, 1947, 1945, 1945, 1946, 
            1946, 1947)), class = "data.frame", row.names = c(NA, -11L))


dat %>% 
  group_by(player) %>% 
  filter(1945 %in% year  & ! 1946 %in% year) %>% 
  select(player) 
#> # A tibble: 2 × 1
#> # Groups:   player [2]
#>   player
#>   <chr> 
#> 1 Albert
#> 2 Barnes

  
dat %>% 
  group_by(player) %>% 
  filter(! 1945 %in% year  & ! 1946 %in% year) %>% 
  select(player) 
#> # A tibble: 2 × 1
#> # Groups:   player [2]
#>   player 
#>   <chr>  
#> 1 Andrews
#> 2 David


dat %>% 
  group_by(player) %>% 
  filter(all(c(1945, 1946) %in% year)) %>% 
  select(player) %>% 
  distinct()
#> # A tibble: 2 × 1
#> # Groups:   player [2]
#>   player
#>   <chr> 
#> 1 Baker 
#> 2 Frank

^{Created on 2022-05-03 by the reprex package (v2.0.1)}