R lubridate within-interval 日期(或間隔)是否在某個間隔內？

a %within% b

int <- interval(ymd("2001-01-01"), ymd("2002-01-01"))
int2 <- interval(ymd("2001-06-01"), ymd("2002-01-01"))

ymd("2001-05-03") %within% int # TRUE
#> [1] TRUE
int2 %within% int # TRUE
#> [1] TRUE
ymd("1999-01-01") %within% int # FALSE
#> [1] FALSE

## recycling (carefully note the difference between using a vector of
## intervals and list of intervals for the second argument)
dates <- ymd(c("2014-12-20", "2014-12-30", "2015-01-01", "2015-01-03"))
blackout_vector <- c(
  interval(ymd("2014-12-30"), ymd("2014-12-31")),
  interval(ymd("2014-12-30"), ymd("2015-01-03"))
)
dates %within% blackout_vector
#> [1] FALSE  TRUE FALSE  TRUE

## within ANY of the intervals of a list
dates <- ymd(c("2014-12-20", "2014-12-30", "2015-01-01", "2015-01-03"))
lst <- list(
  interval(ymd("2014-12-30"), ymd("2014-12-31")),
  interval(ymd("2014-12-30"), ymd("2015-01-03"))
)
dates %within% lst
#> [1] FALSE  TRUE  TRUE  TRUE

## interval within a list of intervals
int <- interval(
  ymd("2014-12-20", "2014-12-30"),
  ymd("2015-01-01", "2015-01-03")
)
int %within% lst
#> [1] FALSE  TRUE