R编程循环差异

Question

我有两列我想以这种方式循环它应该计算（i）的到达 - （i + 1）的出发，并且值应该存储在一个新列中。

departure       arrival 
2012-01-26 08:15:00     2012-01-26 08:50:00 
2012-01-26 11:30:00    2012-01-27 16:00:00 
2012-01-27 18:00:00    2012-01-27 23:05:00 
2012-02-11 00:20:00     2012-02-11 09:10:00 

expected output 
waiting time 
(2012-01-26 08:50:00)-(2012-01-26 11:30:00) = 2 hr 40 min 
(2012-01-27 16:00:00)-(2012-01-27 18:00:00) = 2 hrs 
(2012-01-27 23:05:00)- (2012-02-11 00:20:00)=14 days 13 hrs, 349 hrs 

请帮忙完成上述数据的代码。在RI尝试，但也存在一些误区

for (i :length(data frame){ 
i <- i[17] #index of arrival column 
j <- i+1[18] #index of departure column 
diff = i-j 
return diff 
} 
diff = waiting time 

有在计算到达和离开的区别

我已经转换由POSXClt

Answer 1

这将使用包中的数据出发和到达的一些错误lubridate ：

d$departure <- lubridate::ymd_hms(d$departure) 
d$arrival <- lubridate::ymd_hms(d$arrival) 

d$difference <- d$departure - d$arrival 
d 

  departure    arrival difference 
1 2012-01-26 08:15:00 2012-01-26 08:50:00 -35 mins 
2 2012-01-26 11:30:00 2012-01-27 16:00:00 -1710 mins 
3 2012-01-27 18:00:00 2012-01-27 23:05:00 -305 mins 
4 2012-02-11 00:20:00 2012-02-11 09:10:00 -530 mins