r - Time Difference for a factor variable between two columns on subsequent rows -

i have data frame entry time , exit time. trying column stay duration difference between exit time , next row entry time. dataframe sorted date , entry time.

for first row stay duration is: 6:54:50 - 7:34:36 = 0:39:46

the problem face below scenario: when exit_time 22:15:05 , next row entry_time has 6:02:46. fr case need stay duration 7:47:41

dput(df) structure(list(jrny_id_num = c(115492027250, 115492027250, 115523231209,  115523231209, 115526742250, 115526742250, 115509240124, 115509240124,  115539253765, 115539253765, 115570245886, 115567046025, 115562452408,  115562452408, 115574565032, 115574565032), biz_dt = structure(c(1l,  1l, 1l, 1l, 2l, 2l, 2l, 2l, 3l, 3l, 3l, 3l, 4l, 4l, 4l, 4l), .label = c("2017-01-01",  "2017-01-02", "2017-01-03", "2017-01-04", "2017-01-05", "2017-01-06",  "2017-01-07", "2017-01-09", "2017-01-10", "2017-01-11", "2017-01-12",  "2017-01-13", "2017-01-14", "2017-01-15", "2017-01-16", "2017-01-17",  "2017-01-18", "2017-01-19", "2017-01-20", "2017-01-21", "2017-01-22",  "2017-01-23", "2017-01-24", "2017-01-25", "2017-01-26", "2017-01-27",  "2017-01-31"), class = "factor"), entry_tm = structure(c(37l,  41l, 45l, 46l, 8l, 25l, 52l, 73l, 5l, 15l, 56l, 89l, 29l, 33l,  63l, 77l), .label = c("05:30:39", "05:32:07", "05:32:33", "05:32:38",  "05:32:50", "05:32:59", "05:33:06", "05:37:14", "05:37:58", "05:38:34",  "05:38:38", "05:40:22", "05:40:49", "05:41:16", "05:42:27", "05:47:17",  "05:48:03", "05:48:13", "05:48:54", "05:49:15", "05:50:17", "05:51:42",  "05:52:30", "05:53:20", "05:54:40", "05:56:24", "05:57:59", "06:00:11",  "06:02:46", "06:03:28", "06:05:44", "06:32:18", "06:40:32", "06:40:40",  "06:42:35", "06:45:51", "06:45:55", "06:52:49", "06:57:25", "07:03:49",  "07:34:36", "08:26:43", "09:16:34", "10:16:10", "12:21:51", "13:36:40",  "15:29:30", "16:07:03", "16:10:49", "16:13:51", "16:15:04", "16:29:20",  "16:47:49", "16:48:42", "16:55:50", "16:56:27", "16:58:53", "17:01:02",  "17:03:31", "17:06:19", "17:09:03", "17:11:22", "17:12:15", "17:12:57",  "17:15:11", "17:16:56", "17:21:07", "17:22:18", "17:22:22", "17:23:53",  "17:28:37", "17:30:17", "17:30:24", "17:31:21", "17:32:22", "17:59:07",  "18:16:25", "18:17:13", "18:23:36", "18:27:40", "18:44:43", "18:46:36",  "18:53:21", "20:55:32", "21:06:00", "21:07:08", "21:18:10", "21:18:21",  "21:42:25", "21:43:45", "23:31:38"), class = "factor"), exit_tm = structure(c(34l,  37l, 45l, 46l, 9l, 27l, 54l, 60l, 7l, 20l, 71l, 88l, 25l, 40l,  68l, 72l), .label = c("?", "05:37:56", "05:39:50", "05:39:51",  "05:39:53", "05:40:03", "05:40:51", "05:41:01", "05:43:02", "05:44:51",  "05:45:04", "05:45:45", "05:56:35", "05:57:45", "05:58:58", "06:03:06",  "06:21:39", "06:23:35", "06:24:30", "06:24:58", "06:28:36", "06:29:17",  "06:29:25", "06:32:11", "06:32:15", "06:34:01", "06:36:28", "06:41:02",  "06:41:05", "06:43:31", "06:44:44", "06:51:05", "06:51:46", "06:54:50",  "07:07:55", "07:39:39", "07:43:21", "07:48:49", "08:05:22", "08:17:58",  "08:18:15", "08:32:12", "09:34:23", "10:31:51", "13:17:38", "13:46:19",  "16:08:29", "16:26:21", "16:26:50", "16:37:08", "17:09:13", "17:25:49",  "17:26:31", "17:26:50", "17:27:35", "17:28:20", "17:31:16", "17:34:43",  "17:35:16", "17:36:37", "17:42:09", "17:42:23", "18:00:27", "18:06:53",  "18:08:38", "18:09:18", "18:13:02", "18:14:35", "18:20:15", "18:22:06",  "18:23:17", "18:25:18", "18:25:30", "18:28:47", "18:30:11", "18:30:54",  "18:33:31", "18:38:49", "18:41:19", "18:52:25", "19:05:37", "19:27:49",  "21:06:21", "21:41:28", "21:47:13", "21:53:35", "21:54:29", "22:15:05",  "22:25:41", "23:59:35"), class = "factor")), .names = c("jrny_id_num",  "biz_dt", "entry_tm", "exit_tm"), row.names = c(160l, 73l, 51l,  145l, 111l, 56l, 119l, 157l, 168l, 131l, 81l, 78l, 135l, 35l,  165l, 25l), class = "data.frame") 

the output trying is:

jrny_id_num     biz_dt      entry_tm    exit_tm     stay_duration 115492027250    1/1/2017    6:45:55     6:54:50     0:39:46 115492027250    1/1/2017    7:34:36     7:43:21     4:38:30 115523231209    1/1/2017    12:21:51    13:17:38    0:19:02 115523231209    1/1/2017    13:36:40    13:46:19    15:50:55 115526742250    1/2/2017    5:37:14     5:43:02     0:11:38 115526742250    1/2/2017    5:54:40     6:36:28     9:52:52 115509240124    1/2/2017    16:29:20    17:26:50    0:03:34 115509240124    1/2/2017    17:30:24    17:36:37    11:56:13 115539253765    1/3/2017    5:32:50     5:40:51     0:01:36 115539253765    1/3/2017    5:42:27     6:24:58     10:31:29 115570245886    1/3/2017    16:56:27    18:23:17    3:19:08 115567046025    1/3/2017    21:42:25    22:15:05    7:47:41 115562452408    1/4/2017    6:02:46     6:32:15     0:08:17 115562452408    1/4/2017    6:40:32     8:17:58     8:54:17 115574565032    1/4/2017    17:12:15    18:14:35    0:01:50 115574565032    1/4/2017    18:16:25    18:25:18     

updated

try:

require(dplyr)  diff_to_hms <- function(x) {     y <- abs(x)     sprintf("%s:%02d:%02d:%02d",        ifelse(x < 0, "-", ""),        y %% 86400 %/% 3600,         y %% 3600 %/% 60,         y %% 60 %/% 1)  }  dat %>% mutate(entry_tm = as.posixct(strptime(paste(biz_dt,entry_tm),format = "%y-%m-%d %h:%m:%s")),             exit_tm = as.posixct(strptime(paste(biz_dt,exit_tm),format = "%y-%m-%d %h:%m:%s"))) %>%             mutate(stay_duration = as.numeric(difftime(exit_tm,lead(entry_tm),unit="secs")*-1),                 stay_duration2 = diff_to_hms(stay_duration))