CFCalendarUTC: Coordinated Universal Time CF calendar

In CFtime: Using CF-Compliant Calendars with Climate Projection Data

Coordinated Universal Time CF calendar

Description

This class represents a calendar based on the Coordinated Universal Time. Validity is from 1972 onwards, with dates represented using the Gregorian calendar, up to the present (so future timestamps are not allowed). Leap seconds are considered in all calculations. Also, time zone information is irrelevant and may not be given.

In general, the calendar should use a unit of time of a second. Minute, hour and day are allowed but discouraged. Month and year as time unit are not allowed as there is no practical way to maintain leap second accuracy.

Super classes

CFtime::CFCalendar -> CFtime::CFCalendarProleptic -> CFCalendarUTC

Methods

Public methods

• CFCalendarUTC$new()

• CFCalendarUTC$valid_days()

• CFCalendarUTC$parse()

• CFCalendarUTC$offsets2time()

• CFCalendarUTC$clone()

Inherited methods

• CFtime::CFCalendar$add_day()
• CFtime::CFCalendar$is_compatible()
• CFtime::CFCalendar$is_equivalent()
• CFtime::CFCalendar$print()
• CFtime::CFCalendarProleptic$POSIX_compatible()
• CFtime::CFCalendarProleptic$date2offset()
• CFtime::CFCalendarProleptic$leap_year()
• CFtime::CFCalendarProleptic$month_days()
• CFtime::CFCalendarProleptic$offset2date()

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Method new()

Create a new CF UTC calendar.

Usage

CFCalendarUTC$new(nm, definition)

Arguments

nm

The name of the calendar. This must be "utc".

definition

The string that defines the units and the origin, as per the CF Metadata Conventions.

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Method valid_days()

Indicate which of the supplied dates are valid.

Usage

CFCalendarUTC$valid_days(ymd)

Arguments

ymd

data.frame with dates parsed into their parts in columns year, month and day. Any other columns are disregarded.

Returns

Logical vector with the same length as argument ymd has rows with TRUE for valid days and FALSE for invalid days, or NA where the row in argument ymd has NA values.

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Method parse()

Parsing a vector of date-time character strings into parts. This includes any leap seconds. Time zone indications are not allowed.

Usage

CFCalendarUTC$parse(d)

Arguments

d

character. A character vector of date-times.

Returns

A data.frame with columns year, month, day, hour, minute, second, time zone, and offset. Invalid input data will appear as NA. Note that the time zone is always "+0000" and is included to maintain compatibility with results from other calendars.

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Method offsets2time()

Decompose a vector of offsets, in units of the calendar, to their timestamp values. This adds a specified amount of time to the origin of a CFTime object.

Usage

CFCalendarUTC$offsets2time(offsets = NULL)

Arguments

offsets

Vector of numeric offsets to add to the origin of the calendar.

Returns

A data.frame with columns for the timestamp elements and as many rows as there are offsets.

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Method clone()

The objects of this class are cloneable with this method.

Usage

CFCalendarUTC$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

CFtime documentation built on June 8, 2025, 12:37 p.m.