R：将一个数据帧的结构转换为另一个数据帧的相同结构

目前我有两个大型数据帧，包含超过300000个观察值和100多个变量，但为了简单起见，让我们假设我有df1：

> str(df1)
'data.frame':   3000 obs. of  3 variables:
 $ Name         : chr  "AAA" "BBB" "CCC" "DDD" ...
 $ DateTime     : POSIXct, format: "2014-01-01 00:00:00" "2014-01-01 00:10:00" "2014-01-01 00:20:00" ...
 $ Age          : num  27 25 27 30 ...

df2：

两个数据帧的列数和行数相同，但它们的结构与df2中的所有内容在因子上不同

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我想将df2中的结构转换为与df1相同的结构。请提前告知，谢谢

假设两个数据帧的列的顺序与描述的完全相同，您可以在

映射

方法中使用

类

功能

df2[] <- Map(function(x, y) {
  if (any(grepl("POS", y)))
    ISOdate(as.Date(x), 0, 0, 0)
  else if (y == "Date")
    as.Date(x)
  else
    `class<-`(as.character(x), y)
  }, df2, lapply(df1, class))

转化

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资料

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df1谢谢您的建议！然而，df2中的十六进制和日期时间列分别更改为数字（在chr str中）和1970-01-01。我看到了问题。是否有更多的类，或者
chr、num、POSIXct
是
df1
中唯一的类？在我最初的数据帧中，还有一列的结构为
Date
我们可能需要异常处理。看看编辑是否有用。太棒了！但是，df2中“年龄”列中的值发生了更改…（非常抱歉打扰您）
df2[] <- Map(function(x, y) {
  if (any(grepl("POS", y)))
    ISOdate(as.Date(x), 0, 0, 0)
  else if (y == "Date")
    as.Date(x)
  else
    `class<-`(as.character(x), y)
  }, df2, lapply(df1, class))

lapply(df1, class)
# $name
# [1] "character"
# 
# $date
# [1] "POSIXct" "POSIXt" 
# 
# $age
# [1] "numeric"
# 
# $date2
# [1] "Date"

lapply(df2, class)
# $HEX
# [1] "factor"
# 
# $date
# [1] "factor"
# 
# $age
# [1] "factor"
# 
# $date2
# [1] "factor"

df2[] <- Map(function(x, y) {
  if (any(grepl("POS", y)))
    ISOdate(as.Date(x), 0, 0, 0)
  else if (y == "Date")
    as.Date(x)
  else
    `class<-`(as.character(x), y)
  }, df2, lapply(df1, class))

lapply(df2, class)
# $HEX
# [1] "character"
# 
# $date
# [1] "POSIXct" "POSIXt" 
# 
# $age
# [1] "numeric"
# 
# $date2
# [1] "Date"

df1 <- structure(list(name = c("A", "B", "C", "D", "E"), date = structure(c(1577836800, 
1580515200, 1583020800, 1585699200, 1588291200), class = c("POSIXct", 
"POSIXt")), age = c(30, 27, 25, 28, 23), date2 = structure(c(18262, 
18293, 18322, 18353, 18383), class = "Date")), row.names = c(NA, 
-5L), class = "data.frame")

df2 <- structure(list(HEX = structure(1:5, .Label = c("A", "B", "C", 
"D", "E"), class = "factor"), date = structure(1:5, .Label = c("2020-01-01 01:00:00", 
"2020-02-01 01:00:00", "2020-03-01 01:00:00", "2020-04-01 02:00:00", 
"2020-05-01 02:00:00"), class = "factor"), age = structure(c(5L, 
3L, 2L, 4L, 1L), .Label = c("23", "25", "27", "28", "30"), class = "factor"), 
    date2 = structure(1:5, .Label = c("2020-01-01", "2020-02-01", 
    "2020-03-01", "2020-04-01", "2020-05-01"), class = "factor")), row.names = c(NA, 
-5L), class = "data.frame")