r - 根据原籍国添加营业时间

Question

所以我有一个专栏显示每个 Facebook 帖子的原产国。我也有时间创建帖子。我想做的是为每个阿拉伯帖子增加 3 小时。然后我想为俄罗斯的帖子增加 5 个小时。假设我有 12 个国家需要添加 12 个不同的时区。

语言是R。

allCountries <- c("Arabia" , "Argentina", "Brazil", "Global", "India","Malaysia",
                          "Mexico","Poland","Sweden","Turkey","MaxTurkey","Ukraine","US")

Answer 1

给定

(df <- data.frame(datetime=rep(Sys.time(), 3), origin=c("arabian", "russian", "us")))
#              datetime  origin
# 1 2016-05-04 11:27:52 arabian
# 2 2016-05-04 11:27:52 russian
# 3 2016-05-04 11:27:52      us
offset <- c("arabian"=3, "russian"=5)

然后

transform(df, datetime=datetime + offset[origin]*60*60)
#              datetime  origin
# 1 2016-05-04 14:26:12 arabian
# 2 2016-05-04 16:26:12 russian
# 3                <NA>      us

或者

transform(df, datetime=datetime + ifelse(origin %in% names(offset), offset[df$origin]*60*60, 0))
#              datetime  origin
# 1 2016-05-04 14:27:52 arabian
# 2 2016-05-04 16:27:52 russian
# 3 2016-05-04 11:27:52      us