如何用R语言reshape()函数实现长表转宽表并合并列

需求说明 #

此前提问被标记为重复但未得到清晰解答：需求并非简单长表转宽，而是要将Gender列（取值为Husband/Wife）与stress、satisfaction列组合生成新列（如Husband_stress），且仅能使用R基础包的reshape()函数，不能使用tidyverse等第三方包。

示例输入数据 #

set.seed(2023)

ID<-c(1,1,2,2,3,3,4,4,5,5)
State<-c("NY","NY","NC","NC","TX","TX","VA","VA","SC","SC")
Gender<-c("Husband","Wife","Husband","Wife","Husband","Wife","Husband","Wife","Husband","Wife")
stress<-rnorm(10,0,1)
satisfaction<-rnorm(10,0,1)

data<-data.frame(ID,State,Gender,stress,satisfaction)

期望输出结构 #

ID<-1:5
State<-c("NY","NC","TX","VA","SC")
Husband_stress<-rnorm(5,0,1)
Wife_stress<-rnorm(5,0,1)
Husband_satisfaction<-rnorm(5,0,1)
Wife_satisfaction<-rnorm(5,0,1)

results<-data.frame(ID,State,Husband_stress,Wife_stress,Husband_satisfaction,Wife_satisfaction)

解决方案 #

直接使用基础包的reshape()函数，通过指定分组变量、时间变量和转宽方向即可实现需求：

# 执行转宽操作
results <- reshape(data, 
                   idvar = c("ID", "State"),  # 用于分组的唯一标识变量
                   timevar = "Gender",        # 用于生成列名后缀的变量
                   direction = "wide")        # 指定转宽方向

运行上述代码后，生成的results数据框结构完全符合期望，列名自动生成为Husband_stress、Wife_stress、Husband_satisfaction、Wife_satisfaction的格式，且保留了ID和State作为分组标识。

内容的提问来源于stack exchange，提问作者Tube