data.table无法识别过滤器中的逻辑

在下面的代码片段中,data.table在i中使用时似乎不识别逻辑.

我在最小的例子中重现问题的所有尝试都失败了,这就是我在这里发布完整部分的原因.我希望它与"as.logical(cumsum(CURRENT_TRIP))"部分有关,但只是一种直觉......

# Testdata
timetable <- data.table(rbind(
    c("r1", "t1_1", "p1", 10, 10),
    c("r1", "t1_1", "p2", 11, 11),
    c("r1", "t1_1", "p3", 12, 12),
    c("r1", "t1_1", "p4", 13, 13),
    c("r1", "t1_1", "p5", 14, 14),
    c("r1", "t1_1", "p6", 15, 15),
    c("r1", "t1_1", "p7", 16, 16),
    c("r1", "t1_1", "p8", 17, 17),
    c("r1", "t1_1", "p9", 18, 18),
    c("r1", "t1_1", "p10", 19, 19),

    c("r2", "t2", "p11", 9, 9),
    c("r2", "t2", "p12", 10, 10),
    c("r2", "t2", "p3", 11, 11),
    c("r2", "t2", "p13", 12, 12),
    c("r2", "t2", "p14", 13, 13),
    c("r2", "t2", "p15", 14, 14),
    c("r2", "t2", "p16", 15, 15),
    c("r2", "t2", "p17", 16, 16),
    c("r2", "t2", "p18", 17, 17)
  ))
setnames(timetable, c("ROUTE", "TRIP", "STOP", "ARRIVAL", "DEPARTURE"))
timetable[, ':='(ARRIVAL = as.integer(ARRIVAL), DEPARTURE = as.integer(DEPARTURE))]


# Input
startStation <- "p3"
startTime <- 8

setorder(timetable, TRIP, ARRIVAL)
timetable[, ID := .I]

timetable[,':='(ARR_ROUND_PREV = Inf, ARR_ROUND = Inf, ARR_BEST = Inf, MARKED = F, CURRENT_TRIP = F)]
timetable[STOP == startStation, ':='(ARR_ROUND_PREV = startTime, ARR_ROUND = startTime, ARR_BEST = startTime, MARKED = T)]

routes <- timetable[MARKED == T, unique(ROUTE)] 
ids <- timetable[MARKED == T & DEPARTURE > ARR_ROUND, .(ID = ID[DEPARTURE == min(DEPARTURE)]), by = ROUTE][, ID]

timetable[ID %in% ids, CURRENT_TRIP := T]
timetable[, MARKED := F]

trips <- timetable[CURRENT_TRIP == T, unique(TRIP)]
timetable[TRIP %in% trips, CURRENT_TRIP := as.logical(cumsum(CURRENT_TRIP)), by = TRIP]

# ?
timetable
nrow(timetable[CURRENT_TRIP == T]) #8
sum(timetable$CURRENT_TRIP == T) #15

# but 
nrow(timetable[CURRENT_TRIP > 0]) #15
nrow(timetable[CURRENT_TRIP == 1L]) #15

有任何想法吗？

问题出现在Win 64bit上使用最新的1.9.7和1.9.6以及R 3.2.3

FAB