Question

使用以下数据：

current-group()

使用mutate，我想在第一个唯一PID出现的行上的数据帧（HomeBrand，HomeModel，AutoBrand，AutoModel）中创建四个新列。

结果应如下所示：

data <- data.frame(Name=c("11C","11C","12C","12C","20D","20D"),
               PID=c("AD15E","AD15E","AA05D","AA05D","Z48J","Z48J"),
               Type=c("Home","Auto","Home","Auto","Home","Auto"),
               Brand=c("A","B","C","H","I","D"),
               Model=c("A152","K235","W54","H2","A57","Y0878"))

我尝试过使用mutate，但似乎无法弄清楚

Answer 1

在结果中包含 Home 的 Type 列是没有意义的，因为 Type 列转到标题，对于每行，您混合了 Home 和 Auto 值;没有该列，它只是public class Employee { public int Employee Id { get; set; } public int ManagerId { get; set; } public string FirstName { get; set; } public string LastName { get; set; } [ForeignKey("ManagerId")] public virtual Employee Manager { get; set; } }的简单任务：

reshape

为了比较，这是你的结果：

reshape(data, idvar = c("Name", "PID"), timevar = "Type", direction = "wide") 

#  Name   PID Brand.Home Model.Home Brand.Auto Model.Auto
#1  11C AD15E          A       A152          B       K235
#3  12C AA05D          C        W54          H         H2
#5  20D  Z48J          I        A57          D      Y0878

Answer 2

我们可以使用dcast

执行此操作

library(data.table)
dcast(setDT(data), Name + PID  ~ Type, value.var = c("Brand", "Model"), sep="")
#   Name   PID BrandAuto BrandHome ModelAuto ModelHome
#1:  11C AD15E         B         A      K235      A152
#2:  12C AA05D         H         C        H2       W54
#3:  20D  Z48J         D         I     Y0878       A57

使用mutate创建新数据列

2 个答案: