问是否有一个R函数可以在for循环中使用，用于将数据格式化为文本文件？

EN

mh <- data %>%
 group_by(data$Subject) %>%
 summarise(path = paste(data$y, sep = ",",  collapse = ","),
           days = paste(data$z, sep = ",",  collapse = ","))

Subject  y   z
1        a   2
1        b   5
1        c   7
2        c   5
2        a   10
2        b   12
3        b   4
3        a   9
3        c   14

for(i in 1:3){
  print(cat("Subject",i,"["))
  {  append(data$Subject[i], data$y) 
    print(cat("] ["))
  }
  {   append(data$Subject[i], data$z)  
    print(cat("]\n")) 
  }
}