以%H:%M:%S格式计算时差，格式为R

我试图计算满足特定条件的行的两列之间的时间差

dates1 <- c("1899-12-31 12:20:00 PMT", "1899-12-31 15:30:00 PMT", "1899-12-31 13:20:00 PMT", "1899-12-31 11:50:00 PMT",
             NA)   

dates2 <- c("1899-12-31 11:13:00 PMT", "1899-12-31 11:41:00 PMT", "1899-12-31 14:04:00 PMT", "1899-12-31 13:03:00 PMT", 
            "1899-12-31 13:18:00 PMT")

site <- c(15, 16, 18, 18,
          15)

DS <- as.data.frame(cbind(site, dates1 , dates2))

## convert to POSIXct format
DS[, 2:3] <- lapply(DS[, 2:3], function(x) as.POSIXct(strptime(x,"%Y-%m-%d %H:%M:%S ",tz="")))

## create a new columns with the time difference between dates1 and dates2 in %H:%M:%S format if site=18 , else take value from column dates1
DS$output <- ifelse(DS$site ==18, 
                      difftime(DS$dates1, DS$dates2, units = "mins"),
                      DS$dates1) 

## using the code above doesnt work because:
#1- using the difftime function I can't choose the "%H:%M:%S" for the output
#2- for sites != 18, the dates1 lose its "%H:%M:%S format


# I have also tried to use:
DS$output <- ifelse(DS$site ==18, 
                      difftime(DS$dates1, DS$dates2, units = "mins"),
                      0) 
## and then convert the difference in minutes to %H:%M:%S format using
DS$output<- as.difftime(DS$output , format = "%H:%M:%S", units = "mins")

## but it doesnt work.

## the output should be something like:

output<- c("12:20:00", "15:30:00","00:44:00", "01:13:00", NA)

DS.out <- cbind(DS, output)

> DS.out 
  site                  dates1                  dates2   output
1   15 1899-12-31 12:20:00 PMT 1899-12-31 11:13:00 PMT 12:20:00
2   16 1899-12-31 15:30:00 PMT 1899-12-31 11:41:00 PMT 15:30:00
3   18 1899-12-31 13:20:00 PMT 1899-12-31 14:04:00 PMT 00:44:00
4   18 1899-12-31 11:50:00 PMT 1899-12-31 13:03:00 PMT 01:13:00
5   15                    <NA> 1899-12-31 13:18:00 PMT     <NA>

    #Where output is the time difference calculated for rows 3 and 4 (site=18) 
#or a copy of the time from dates 1 for the other rows (with sites different from 18). 

---

dates1喜欢这件作品吗

with(DS, ifelse(site == 18, as.character(lubridate::seconds_to_period(
                difftime(dates2, dates1, units = "secs"))), 
                format(dates1, "%T")))

#[1] "12:20:00"  "15:30:00"  "44M 0S"    "1H 13M 0S" NA   

您可以使用chron库中的“times”格式

（这不是很简单，但似乎有效）

#以分钟计算差异
DS$Time1NEW您可以在小时内使用
difftime
<代码>楼层
和
%%1
中的每个小时和分钟都可以
粘贴在一起。不过，还需要一些舍入

DS$output[DS$site == 18] <- {
  tmp <- as.numeric(round(with(DS[DS$site == 18, ], difftime(dates2, dates1, units="hours")), 2))
  paste(sprintf("%02d", floor(tmp)), round(tmp %% 1 * 60), "00", sep=":")
}
DS$output[site != 18] <- strftime(DS$dates1[DS$site != 18], "%T")
DS
#   site              dates1              dates2   output
# 1   15 1899-12-31 12:20:00 1899-12-31 11:13:00 12:20:00
# 2   16 1899-12-31 15:30:00 1899-12-31 11:41:00 15:30:00
# 3   18 1899-12-31 13:20:00 1899-12-31 14:04:00 00:44:00
# 4   18 1899-12-31 11:50:00 1899-12-31 13:03:00 01:13:00
# 5   15                <NA> 1899-12-31 13:18:00     <NA>

DS$output[DS$site==18]您可以使用
hms
库

require(hms)
x <- data.frame(TIME_SPENT = as.difftime(runif(10) * 10, format = 'H', units = 'hours'))
x$TIME_SPENT_HMS <- hms(hours = as.numeric(x$TIME_SPENT))

> x
      TIME_SPENT  TIME_SPENT_HMS
1  0.670335 hours 00:40:13.206023
2  6.740590 hours 06:44:26.122495
3  9.433242 hours 09:25:59.670743
4  9.350243 hours 09:21:00.873019
5  1.459504 hours 01:27:34.214544
6  4.820711 hours 04:49:14.560171
7  5.052186 hours 05:03:07.870653
8  9.415136 hours 09:24:54.489527
9  4.717802 hours 04:43:04.086949
10 4.131969 hours 04:07:55.087836

您可以对其执行各种计算

> x$TIME_SPENT_HMS[1] + 10
Time difference of 2423.206 secs

表视图中显示的值也用分号表示：

您是否考虑过lubridate
软件包？在中，我找不到以H%：%M:%S格式计算时间差的函数lubridate@RonakShah我刚刚更新了示例以包含预期的输出。我加入了一个较小的数据集，以便于理解。谢谢，但是如何将“4400”转换为00:44:00？我需要他们在相同的格式做一些分析后，数据集是big@AnaAntunes如果您想对它们进行分析，这两种格式都没有用处，因为它们只是字符串。如果您希望所有内容都采用相同的格式，那么更改
日期1的格式如何<代码>带有（DS，ifelse（site==18，as.character）（lubridate:：seconds\u to_period（difftime（dates2，dates1，units=“secs”）），格式（dates1，“%HH%MM%SS”））
是日期的格式完全相同。但是如果我想从“%HH%MM%SS”更改为“%H:%M:%S”，我该怎么做呢？如果我使用格式（DS$output，“%H:%M:%S”），但它给了我一个错误：格式错误。默认值（其他站点$Time1NEW，“%H:%M:%S”）：无效的“修剪”参数这也是一个不错的方法。谢谢
require(hms)
x <- data.frame(TIME_SPENT = as.difftime(runif(10) * 10, format = 'H', units = 'hours'))
x$TIME_SPENT_HMS <- hms(hours = as.numeric(x$TIME_SPENT))

> x
      TIME_SPENT  TIME_SPENT_HMS
1  0.670335 hours 00:40:13.206023
2  6.740590 hours 06:44:26.122495
3  9.433242 hours 09:25:59.670743
4  9.350243 hours 09:21:00.873019
5  1.459504 hours 01:27:34.214544
6  4.820711 hours 04:49:14.560171
7  5.052186 hours 05:03:07.870653
8  9.415136 hours 09:24:54.489527
9  4.717802 hours 04:43:04.086949
10 4.131969 hours 04:07:55.087836

> class(x$TIME_SPENT_HMS)
[1] "hms"      "difftime"

> x$TIME_SPENT_HMS[1] + 10
Time difference of 2423.206 secs