如何识别周末并从我的 R 时差中自动减去它

Question

我正在编写一个代码，该代码使用两个时间戳向量来为我提供特定进程所需的时间（简称 difftime）。

不过周末时间应该是暂停的。因此，如果产品在周五进货并在周二离开，我必须减去周末时间。所以我需要一种可能性来确定产品处理时间何时经过周末，周末会自动从时差中减去。

这些产品的识别比减法更难。

Answer 1

函数 weekdays 可能对这里有帮助：

weekdays(as.Date("2018-07-30"))
# [1] "monday"

因此，如果您传递一个日期对象向量，您将能够识别星期六和星期日。

例如：

which(weekdays(as.Date(c("2018-07-30", "2018-07-29", "2018-07-28", "2018-07-27"))) %in% c("saturday", "sunday"))
[1] 2 3

Answer 2

使用 chron 包中的 is.weekend。

days<-seq.Date(as.Date("01-01-2017",format= "%d-%m-%Y"),as.Date("01-04-2017",format= "%d-%m-%Y"),by = "days")   
library(chron)  
  days[is.weekend(days)]
  [1] "2017-01-01" "2017-01-07" "2017-01-08" "2017-01-14" "2017-01-15" "2017-01-21" "2017-01-22"
  [8] "2017-01-28" "2017-01-29" "2017-02-04" "2017-02-05" "2017-02-11" "2017-02-12" "2017-02-18"
 [15] "2017-02-19" "2017-02-25" "2017-02-26" "2017-03-04" "2017-03-05" "2017-03-11" "2017-03-12"
 [22] "2017-03-18" "2017-03-19" "2017-03-25" "2017-03-26" "2017-04-01"

  weekdays.Date(days[is.weekend(days)])
  [1] "Sunday"   "Saturday" "Sunday"   "Saturday" "Sunday"   "Saturday" "Sunday"   "Saturday"
  [9] "Sunday"   "Saturday" "Sunday"   "Saturday" "Sunday"   "Saturday" "Sunday"   "Saturday"
 [17] "Sunday"   "Saturday" "Sunday"   "Saturday" "Sunday"   "Saturday" "Sunday"   "Saturday"
 [25] "Sunday"   "Saturday"

如何识别周末并从我的 R 时差中自动减去它

How to Identify a Weekend and Subtract it Automatically From my Time Differences in R

r

difftime