将日期格式更改为"%d /%m /%Y"

Question

想改变日期格式.我的数据框如下所示,并希望将所有日期格式更改为"%d/%m/%Y".

DF:

id    bdate       wdate        ddate
1   09/09/09    12/10/09     2009-09-27

Answer 1

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

Answer 2

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")