## Date Date Compare Date -> logical + Date -> Date Date - Date -> difftime Date + numeric -> Date Date - numeric -> Date Date + difftime -> Date Date - difftime -> Date numeric + Date -> Date difftime + Date -> Date## POSIXt POSIXt Compare POSIXt -> logical + POSIXt -> POSIXt POSIXt - POSIXt -> difftime POSIXt + numeric -> POSIXt POSIXt - numeric -> POSIXt POSIXt + difftime -> POSIXt POSIXt - difftime -> POSIXt numeric + POSIXt -> POSIXt difftime + POSIXt -> POSIXt
## difftime difftime Compare difftime -> logical + difftime -> difftime - difftime -> difftime difftime + difftime -> difftime difftime - difftime -> difftime difftime + numeric -> difftime difftime - numeric -> difftime numeric + difftime -> difftime numeric - difftime -> difftime difftime * numeric -> difftime difftime / numeric -> difftime numeric * difftime -> difftime
Date | a Date object. |
POSIXt | a POSIXt object. |
difftime | a difftime object. |
numeric | a numeric object. |
logical | a logical object. |
Compare | a logic operator including "<", ">", "!=", "==", "<=" and ">=". |
## Date as.Date("2038-01-19") > as.Date("1970-01-01") as.Date("2038-01-19") - as.Date("1970-01-01") as.Date("1970-01-01") + (as.Date("2038-01-19") - as.Date("1970-01-01")) as.Date("1970-01-01") + 1 as.Date("1970-01-01") + as.difftime(1, units = "weeks")## POSIXt as.POSIXct("2038-01-19 03:14:07") > as.POSIXct("1970-01-01 00:00:00") as.POSIXct("2038-01-19 03:14:07") - as.POSIXct("1970-01-01 00:00:00") as.POSIXct("1970-01-01 00:00:00") + (2^31 - 1) as.POSIXct("1970-01-01 00:00:00") + 1 as.POSIXct("1970-01-01 00:00:00") + as.difftime(1, units = "weeks")
## difftime (df1 <- as.difftime(12, units = "hours")) (df2 <- as.difftime(1, units = "days")) df1 * 2 == df2 df1 + 12 df2 / 2