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Is x a leap year?

Source: R/is_leap_year.R
is_leap_year.Rd

Tests whether a date or year is a leap year.

For years outside [1000,3000), this returns NA.

This is an S3 generic. This package provides methods for:

  • numeric types double and integer (interpreted as years), and

  • date types datey, Date, POSIXct and POSIXlt.

Usage

is_leap_year(x, ...)

# Default S3 method
is_leap_year(x, ...)

# S3 method for class 'integer'
is_leap_year(x, ...)

# S3 method for class 'double'
is_leap_year(x, ...)

# S3 method for class 'datey'
is_leap_year(x, ...)

# S3 method for class 'Date'
is_leap_year(x, ...)

# S3 method for class 'POSIXct'
is_leap_year(x, ...)

# S3 method for class 'POSIXlt'
is_leap_year(x, ...)

Arguments

x

A vector date type or numeric year.

...

Other arguments (not used in this package).

Value

NA if x is not interpretable as a year or date, or outside [1000,3000), TRUE if x is a leap year, otherwise FALSE.

Examples

any(is_leap_year(c(1900, 1901, 2001))) #FALSE
#> [1] FALSE
all(is_leap_year(c(1904.1, 2000.5, 2004.9))) #TRUE
#> [1] TRUE