如何创建/合并面板数据？

Question

我有两个数据框。数据框“天气”如下所示：

weather<-data.frame(Date=c("2012-04-01","2012-04-02","2012-04-03","2012-04-04"),Day=c("Sunday","Monday","Tuesday","Wednesday"), Temp=c(86,89,81,80))

Date       Day       Temp    
2012-04-01 Sunday     86
2012-04-02 Monday     89
2012-04-03 Tuesday    81
2012-04-04 Wednesday  80

而且，数据框“Regularity”如下所示：

Regularity<-data.frame(Date=c("2012-04-02","2012-04-04","2012-04-03","2012-04-04"),EmployeeID=c(1,1,2,2),Attendance=c(1,1,1,1))

Date        EmployeeID Attendance
2012-04-02           1          1
2012-04-04           1          1
2012-04-03           2          1
2012-04-04           2          1

我想用 R 格式创建一个面板数据框：

Date       Day       Temperature EmployeeID Attendence  
2012-04-01 Sunday     86              1         0
2012-04-02 Monday     89              1         1
2012-04-03 Tuesday    81              1         0
2012-04-04 Wednesday  80              1         1
2012-04-01 Sunday     86              2         0
2012-04-02 Monday     89              2         0
2012-04-03 Tuesday    81              2         1
2012-04-04 Wednesday  80              2         1

我已经尝试过 merge 和 reshape2，但没有成功。我将非常感谢任何帮助。谢谢。

Answer 1

您可以使用双 merge 和 expand.grid，如下所示：

merge(weather, 
      merge(Regularity, 
            expand.grid(Date = unique(weather$Date), 
                        EmployeeID = unique(Regularity$EmployeeID)), 
            all = TRUE))
#         Date       Day Temp EmployeeID Attendance
# 1 2012-04-01    Sunday   86          1         NA
# 2 2012-04-01    Sunday   86          2         NA
# 3 2012-04-02    Monday   89          1          1
# 4 2012-04-02    Monday   89          2         NA
# 5 2012-04-03   Tuesday   81          1         NA
# 6 2012-04-03   Tuesday   81          2          1
# 7 2012-04-04 Wednesday   80          1          1
# 8 2012-04-04 Wednesday   80          2          1

expand.grid 步骤是获取完整数据集所需的“日期”和“员工 ID”的所有组合。

您可以在另一个步骤中轻松地将 NA 值替换为“0”。