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Gregorian cyclical time representations

Source: R/cal_gregorian.R
cyclical_gregorian.Rd

Cyclical time representations for the Gregorian calendar system. These functions create time objects that repeat within a larger time cycle, useful for identifying seasonal patterns or positions within a calendar period.

Usage

month_of_year(.data, tz = NULL, discrete = TRUE)

day_of_year(.data, tz = NULL, discrete = TRUE)

day_of_month(.data, tz = NULL, discrete = TRUE)

Arguments

.data

Another object to be coerced into the specified cyclical time.

tz

Timezone, defaults to "UTC".

discrete

If TRUE, the position within the cycle that .data falls into is returned as an integer. If FALSE, a fractional position is returned (analagous to time using a continuous time model).

Details

  • month_of_year(): Represents the month position within a year (1-12). The chronon is one month, cycling within a year.

  • day_of_year(): Represents the day position within a year (1-365 or 1-366 for leap years). The chronon is one day, cycling within a year.

  • day_of_month(): Represents the day position within a month (1-28, 1-29, 1-30, or 1-31 depending on the month). The chronon is one day, cycling within a month.

These cyclical representations are useful for analyzing seasonal patterns or comparing time points at similar positions across different years.

Custom Gregorian cyclical time representations

You can create custom cyclical time representations using cyclical_time() with any of the supported Gregorian time units (see calendar_gregorian).

For example, to create a representation for day of the month:

day_of_month <- cyclical_time(
  chronon = tu_day(1L),
  cycle = tu_month(1L)
)

See also

linear_gregorian for linear Gregorian time representations, cyclical_time() for creating custom cyclical time representations

Examples


month_of_year(Sys.Date())
#> <mixtime[1]>
#> [1] Dec


day_of_year(Sys.Date())
#> <mixtime[1]>
#> [1] D353-0.0%