r - 我如何在 R 中创建一个 data.frame 玩家在游戏中一起开始的次数

Question

我刚刚开始研究网络分析，并想从创建一个数据框架开始，该框架显示团队中的篮球运动员一起开始的频率

理想情况下，我想合并来自 purrr 的 map 功能

所以以此作为输入

game_1 <- c("Andy","Bob","Chris","Doug","Evan") 
game_2 <- c("Andy","Chris","Evan","Fred","George")  

我想要这样的结果

n_1  n_2 games

Andy  Bob    1
Andy  Chris  2
Andy  Doug   1
Andy  Evan   2
Andy  Fred   1
Andy  George 1
Bob   Chris  1
Bob   Doug   1
Bob   Evan   1
Chris Doug   1
Chris Evan   2
Chris Fred   1
Chris George 1
Doug  Evan   1
Evan  Fred   1
Evan  George 1
Fred  George 1

Answer 1

library(dplyr)

# get combinations from game_1
g1 <- combn(game_1, 2) %>% t 

# get combinations from game_2
g2 <- combn(game_2, 2) %>% t 

# bind both in a dataframe and count pairs
g1 %>% 
  rbind.data.frame(g2) %>% 
  group_by(V1, V2) %>% 
  summarise(games = n())

# A tibble: 17 x 3
# Groups:   V1 [?]
       V1     V2 games
   <fctr> <fctr> <int>
 1   Andy    Bob     1
 2   Andy  Chris     2
 3   Andy   Doug     1
 4   Andy   Evan     2
 5   Andy   Fred     1
 6   Andy George     1
 7    Bob  Chris     1
 8    Bob   Doug     1
 9    Bob   Evan     1
10  Chris   Doug     1
11  Chris   Evan     2
12  Chris   Fred     1
13  Chris George     1
14   Doug   Evan     1
15   Evan   Fred     1
16   Evan George     1
17   Fred George     1