将具有相同日期的特定行添加到数据框中答案

【问题标题】：Adding specific rows with the same date into a dataframe将具有相同日期的特定行添加到数据框中
【发布时间】：2021-06-21 17:36:29
【问题描述】：

我有两个数据框，例如：

head (df1)
           Date    v1     v2     v3
       2007-01-01  1      1      Yes
       2007-01-02  2      1      Yes
       2007-01-03  2     1      Yes
       2007-01-04  12     1      Yes
       2007-01-05  3      1      Yes

还有：

head (df2)
           Date    v1     v2     v3
       2007-01-01  1      1      No
       2007-01-01  2      1      No
       2007-01-04  12     1      No
       2007-01-05  3      1      No

我想添加从df2 到df1 的行仅如果它们具有相同的日期。最终的 df 应该是这样的：

           Date    v1     v2     v3
       2007-01-01  1      1      Yes
       2007-01-01  1      1      No
       2007-01-01  2      1      No
       2007-01-02  2      1      Yes
       2007-01-03  2      1      Yes
       2007-01-04  12     1      Yes
       2007-01-04  12     1      No
       2007-01-05  3      1      Yes
       2007-01-05  3      1      No
 
I'm sure there is a simple way to do this, I just can't quite find it.

【问题讨论】：

标签： r merge

【解决方案1】：

我们可以根据'df1'和rbind中的'Date'列对'df2'中的'Date'进行子集化

out <- rbind(df1, subset(df2, Date %in% df1$Date))
out[order(out$Date),]

-输出

 Date v1 v2  v3
1 2007-01-01  1  1 Yes
6 2007-01-01  1  1  No
7 2007-01-01  2  1  No
2 2007-01-02  2  1 Yes
3 2007-01-03  2  1 Yes
4 2007-01-04 12  1 Yes
8 2007-01-04 12  1  No
5 2007-01-05  3  1 Yes
9 2007-01-05  3  1  No

或使用dplyr

library(dplyr)
bind_rows(df1, filter(df2, Date %in% df1$Date)) %>% 
   arrange(Date)

数据

df1 <- structure(list(Date = c("2007-01-01", "2007-01-02", "2007-01-03", 
"2007-01-04", "2007-01-05"), v1 = c(1L, 2L, 2L, 12L, 3L), v2 = c(1L, 
1L, 1L, 1L, 1L), v3 = c("Yes", "Yes", "Yes", "Yes", "Yes")), 
class = "data.frame", row.names = c(NA, 
-5L))

df2 <- structure(list(Date = c("2007-01-01", "2007-01-01", "2007-01-04", 
"2007-01-05"), v1 = c(1L, 2L, 12L, 3L), v2 = c(1L, 1L, 1L, 1L
), v3 = c("No", "No", "No", "No")), 
class = "data.frame", row.names = c(NA, 
-4L))

【讨论】：

完美，这是一种享受。谢谢！