Check If an Object Is of Type Date

Check if the given x is of any known Date type.

IsDate(x, what = c("either", "both", "timeVaries"))

Arguments

x

a vector or values to be checked.

what

can be any value out of "either" (default), "both" or "timeVaries".

Details

This checks for many known Date and Time classes: "POSIXt", "POSIXct", "dates", "times", "chron", "Date".

Value

logical vector of the same dimension as x.

Author

Frank E Harrell

See also

Year, Month, etc.

Examples

IsDate(as.Date("2013-04-10"))
#> [1] TRUE

IsDate(31002)
#> [1] FALSE