Date 将日期格式更改为"；%d/%m/%Y“；_Date_R_Formatting

Date 将日期格式更改为"；%d/%m/%Y“；

date r formatting

Date 将日期格式更改为"；%d/%m/%Y“；,date,r,formatting,Date,R,Formatting,要更改日期格式。我的数据框如下所示，希望将所有日期格式更改为“%d/%m/%Y” df: df$ddatedf$ddateDefaultR操作是将字符串视为因素。当然，单个设置可能不同于默认设置。最好将变量值更改为字符，然后将其转换为日期。我经常使用chronpackage——它很好，很简单，最重要的是，它能完成任务。这个软件包的唯一缺点在于时区处理如果未安装chron，请执行以下操作： install.packages("chron") # load it library(chron)

要更改日期格式。我的数据框如下所示，希望将所有日期格式更改为

“%d/%m/%Y”

df:

df$ddatedf$ddateDefaultR
操作是将字符串视为因素。当然，单个设置可能不同于默认设置。最好将变量值更改为字符
，然后将其转换为日期
。我经常使用chron
package——它很好，很简单，最重要的是，它能完成任务。这个软件包的唯一缺点在于时区处理
如果未安装chron
，请执行以下操作：
 install.packages("chron")
 # load it
 library(chron)
 # make dummy data
 bdate <- c("09/09/09", "12/05/10", "23/2/09")
 wdate <- c("12/10/09", "05/01/07", "19/7/07")
 ddate <- c("2009-09-27", "2007-05-18", "2009-09-02")
 # notice the last argument, it will not allow creation of factors!
 dtf <- data.frame(id = 1:3, bdate, wdate, ddate, stringsAsFactors = FALSE)
 # since we have characters, we can do:
 foo <- transform(dtf, bdate = chron(bdate, format = "d/m/Y"), wdate = chron(wdate, format = "d/m/Y"), ddate = chron(ddate, format = "y-m-d"))
 # check the classes
 sapply(foo, class)
 # $id
 # [1] "integer"

 # $bdate
 # [1] "dates" "times"

 # $wdate
 # [1] "dates" "times"

 # $ddate
 # [1] "dates" "times"

install.packages（“chron”）
#加载它
图书馆（计时）
#制作虚拟数据
b它几乎不取决于数据.frame中的实际内容。这些字段是日期
，字符
，系数
？如果您想更改数据.frame
的打印方式，则可以重载打印
方法（打印.Date
或打印.POSIXlt）中的一种方法。您好，Marek，这些是日期！BazonBut类更改为角色。我如何保持上课的日期？
df$ddate<-strftime(df$ddate,"%d/%m/%Y")
df$bdate<-strftime(strptime(df$bdate,"%d/%m/%y"),"%d/%m/%Y")
df$wdate<-strftime(strptime(df$wdate,"%d/%m/%y"),"%d/%m/%Y")

df$ddate <- format(as.Date(df$ddate), "%d/%m/%Y")

 install.packages("chron")
 # load it
 library(chron)
 # make dummy data
 bdate <- c("09/09/09", "12/05/10", "23/2/09")
 wdate <- c("12/10/09", "05/01/07", "19/7/07")
 ddate <- c("2009-09-27", "2007-05-18", "2009-09-02")
 # notice the last argument, it will not allow creation of factors!
 dtf <- data.frame(id = 1:3, bdate, wdate, ddate, stringsAsFactors = FALSE)
 # since we have characters, we can do:
 foo <- transform(dtf, bdate = chron(bdate, format = "d/m/Y"), wdate = chron(wdate, format = "d/m/Y"), ddate = chron(ddate, format = "y-m-d"))
 # check the classes
 sapply(foo, class)
 # $id
 # [1] "integer"

 # $bdate
 # [1] "dates" "times"

 # $wdate
 # [1] "dates" "times"

 # $ddate
 # [1] "dates" "times"