我在R中还很陌生,需要一些帮助。我有两个具有相当相似信息的数据框。第一个数据框包含有关航空公司错误连接的信息,而另一个数据框是同一航空公司的完整时间表。现在,我需要在misconnection data.frame中添加一个新列,其中包括时间表中的航班,可以代替转机中的延迟航班。
我要替换的航班需要满足一系列条件(在一定的时间范围内,必须在同一工作日,并且需要飞往相同的目的地)。另外,我希望R选择(按时间)离运输途中的新到达时间最近的航班(来自错误连接data.frame)。
错误连接data.frame如下所示(总共1620行):
miscon <- data.frame(flight.date = as.Date(c("2019-08-05", "2019-10-03", "2019-07-21", "2019-05-29"), format="%Y-%m-%d"),
Outbound.airport = c("MXP", "KRK", "KLU", "OTP"),
arr.time = as.POSIXct(c("19:25:00", "20:52:00", "07:33:00", "18:49:00"), format="%H:%M:%S"),
next.pos.dep = as.POSIXct(c("19:36:00", "21:17:00", "07:58:00", "19:14:00"), format="%H:%M:%S"),
weekday = c("4", "7", "7", "3"))
view(miscon)
flight.date Outbound.airport arr.time next.pos.dep Weekday
1 2019-08-05 MXP 19:25:00 19:36:00 4
2 2019-10-03 KRK 20:52:00 21:17:00 7
3 2019-07-21 KLU 07:33:00 07:58:00 7
4 2019-05-29 OTP 18:49:00 19:14:00 3
时间表data.frame看起来像这样:
tt <- data.frame(start.date = as.Date(c("2019-03-25", "2019-05-02", "2019-07-30", "2019-05-29"), format="%Y-%m-%d"),
end.date = as.Date(c("2019-10-21", "2019-10-27", "2019-08-26", "2019-06-01"), format="%Y-%m-%d"),
weekday = c("1234567", "1.3..67", "1.34567", "..3.5.."),
Outbound.airport = c("KLU", "KLU", "MXP", "OTP"),
dep.time = as.POSIXct(c("12:20:00", "15:55:00", "19:55:00", "20:34:00"), format="%H:%M:%S"))
view(tt)
start.date end.date Weekday Outbound.airport dep.time
1 2019-03-25 2019-10-21 1234567 KLU 12:20:00
2 2019-05-02 2019-10-27 1.3..67 KLU 15:55:00
3 2019-07-30 2019-08-26 1.34567 MXP 19:55:00
4 2019-03-30 2019-06-01 ..3.5.. OTP 20:34:00
在Excel中,我已经使用索引匹配解决了此问题。但是,对于excel来说,问题有点大,这就是为什么我需要将其转换为R的原因。尝试在R中使用match和mutate函数,但似乎我要匹配的值必须相等-我这样做没想到我的会是。
还使用DescTools软件包找到了解决类似问题的有趣解决方案,但我尝试将其成功实现。
get_close2 <- function(xx=tt, yy=miscon) {
pos <- vector(mode = "numeric")
for(i in 1:dim(yy)[1]) {
pos[i] <- DescTools::Closest(xx$dep.time, yy$next.pos.dep[i])
#print(pos[i])
yy$new.flight[i] <- pos[i]
}
out <- yy
return(out)
}
get_close2()
为此,我只尝试了一种情况。它生成了一个列,但仅包含NA。显然,我现在很遥远,这就是为什么我要寻求帮助。希望问题是清楚的。最终结果最好如下所示:
miscon
flight.date Outbound.airport arr.time next.pos.dep Weekday new.flight.time
1 2019-12-05 MXP 19:25:00 19:36:00 4 19:55:00
2 2019-10-03 KRK 20:52:00 21:17:00 7 NA
3 2019-07-21 KLU 07:33:00 07:58:00 7 12:20:00
4 2019-05-29 OTP 18:49:00 19:14:00 3 20:34:00
[好吧,这并不漂亮,但是您有一个相当复杂的问题,而且对于我所寻找的东西,这还不是很清楚-您需要在比提供的小示例更大的数据集上进行检查。确定第一。
# setup
library(data.table)
setDT(tt)
setDT(miscon)
# make tt long format splitting weekdays out
tt <- melt(tt[, paste("V", 1:7, sep = "") := tstrsplit(weekday, "")][, -"weekday"], measure.vars = paste("V", 1:7, sep = ""))[value != "."][, c("weekday", "value", "variable") := .(value, NULL, NULL)]
# join, calculate time difference, convert format of times, rank on new.dep.time within group, and filter
newDT <- miscon[tt, on = c("Outbound.airport", "weekday"), nomatch = 0][
, new.dep.time := as.numeric(dep.time - arr.time)][
, c("arr.time", "dep.time", "next.pos.dep") := .(format(arr.time, "%H:%M"), format(dep.time, "%H:%M"), format(next.pos.dep, "%H:%M"))][
, new.dep.rank := rank(new.dep.time), by = c("Outbound.airport", "weekday")][
new.dep.rank == 1, -c("new.dep.rank", "new.dep.time")]
我认为您可以按照以下步骤进行操作。首先,我将重新排列Weekday
列,以便在航班进行的每个工作日都有一行:
library(data.table)
library(dplyr)
library(tidyr)
tt <- tt %>% separate(weekday, into = as.character(1:7), sep = 1:6) %>%
gather(key="key", value="weekday", -c(start.date, end.date, Outbound.airport, dep.time)) %>%
filter(weekday %in% 1:7) %>%
select(-key)
然后我将在机场和工作日左转miscon
和tt
。
tt <- data.table(tt)
miscon <- data.table(miscon)
setkey(miscon, Outbound.airport, weekday)
setkey(tt, Outbound.airport, weekday)
df <- tt[miscon]
现在您具有所有可能连接的data.frame。剩下的唯一事情就是找到每个连接的两次飞行之间的最短时间。
df[,timediff:= dep.time-arr.time, by=.(weekday, Outbound.airport)]
现在您可以按最小时间延迟(timediff
)过滤行:
df = df[ , .SD[which.min(timediff)], by=.(weekday, Outbound.airport, flight.date, arr.time, next.pos.dep)]
setnames(df, "dep.time", "new.flight.time")
> df
weekday Outbound.airport flight.date arr.time next.pos.dep start.date end.date new.flight.time timediff
1: 7 KLU 2019-07-21 2020-04-27 07:33:00 2020-04-27 07:58:00 2019-03-25 2019-10-21 2020-04-27 12:20:00 17220 secs
2: 4 MXP 2019-08-05 2020-04-27 19:25:00 2020-04-27 19:36:00 2019-07-30 2019-08-26 2020-04-27 19:55:00 1800 secs
3: 3 OTP 2019-05-29 2020-04-27 18:49:00 2020-04-27 19:14:00 2019-05-29 2019-06-01 2020-04-27 20:34:00 6300 secs
解决方案是dplyr
和data.table
的混合体。