使用 ID 和匹配字符串合并两个数据框

Question

假设我有2个数据框：

df1 <- data.frame(eventId = c("6770583", "6770529"), home = c("Real Salt Lake", "Vancouver Whitecaps Fc"), away = c("New England Revolution", "Sporting Kansas City"))

df2 <- data.frame(eventId = c("6770583", "6770583", "6770529", "6770529"), currentOddType = c("New England Revolution to win 1-0, 2-0 or 2-1", "Real Salt Lake to win 1-0, 2-0 or 2-1", "Sporting Kansas City to win 1-0, 2-0 or 2-1", "Vancouver Whitecaps to win 1-0, 2-0 or 2-1"), currentOdds = c("7", "4", "4.33", "4.5"))

我想使用 eventId 和团队名称合并它们，因为 eventId 在 df2 中重复。

期望的结果如下所示：

dfFinal <- data.frame(eventId = c("6770583", "6770529"), home = c("Real Salt Lake", "Vancouver Whitecaps Fc"), away = c("New England Revolution", "Sporting Kansas City"), homeOdd = c("4", "4.5"), awayOdd = c("7", "4.33"))

dfFinal

此外，如果没有匹配项，homeOdd 和 awayOdd 将是 "NAs"

Answer 1

我们可以结合使用 gather/spread 和 left_join

df1 %>%
    gather(type, team, -eventId) %>%
    left_join(
        df2 %>%
            separate(currentOddType, into = c("team", "type"), sep = "\s(?=to win)") %>%
            select(eventId, team, currentOdds),
        by = c("eventId", "team")) %>%
    unite(val, team, currentOdds) %>%
    spread(type, val) %>%
    separate(away, into = c("away", "awayOdd"), sep = "_") %>%
    separate(home, into = c("home", "homeOdd"), sep = "_")
#  eventId                   away awayOdd                   home homeOdd
#1 6770529   Sporting Kansas City    4.33 Vancouver Whitecaps Fc      NA
#2 6770583 New England Revolution       7         Real Salt Lake       4

请注意，Vancouver Whitecaps Fc 变为 NA，因为 df1 和 df2 中的名称不同（Vancouver Whitecaps Fc 与 Vancouver Whitecaps）。

使用 ID 和匹配字符串合并两个数据框

Merge two data frames using ID and matching string

merge

if-statement

r

stringr

grepl