This class represents a standard calendar of 365 or 366 days per year. This calendar is compatible with the standard POSIXt calendar for periods after the introduction of the Gregorian calendar, 1582-10-15 00:00:00. The calendar starts at 0001-01-01 00:00:00, e.g. the start of the Common Era.
Note that this calendar, despite its name, is not the same as that used in ISO8601 or many computer systems for periods prior to the introduction of the Gregorian calendar. Use of the "proleptic_gregorian" calendar is recommended for periods before or straddling the introduction date, as that calendar is compatible with POSIXt on most OSes.
CFtime::CFCalendar
-> CFCalendarStandard
new()
Create a new CF calendar.
CFCalendarStandard$new(nm, definition)
nm
The name of the calendar. This must be "standard" or "gregorian" (deprecated).
definition
The string that defines the units and the origin, as per the CF Metadata Conventions.
A new instance of this class.
valid_days()
Indicate which of the supplied dates are valid.
CFCalendarStandard$valid_days(ymd)
ymd
data.frame
with dates parsed into their parts in columns
year
, month
and day
. Any other columns are disregarded.
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.
is_gregorian_date()
Indicate which of the supplied dates are in the Gregorian part of the calendar, e.g. 1582-10-15 or after.
CFCalendarStandard$is_gregorian_date(ymd)
ymd
data.frame
with dates parsed into their parts in columns
year
, month
and day
. Any other columns are disregarded.
Logical vector with the same length as argument ymd
has rows
with TRUE
for days in the Gregorian part of the calendar and FALSE
otherwise, or NA
where the row in argument ymd
has NA
values.
POSIX_compatible()
Indicate if the time series described using this calendar
can be safely converted to a standard date-time type (POSIXct
,
POSIXlt
, Date
). This is only the case if all offsets are for
timestamps fall on or after the start of the Gregorian calendar,
1582-10-15 00:00:00.
CFCalendarStandard$POSIX_compatible(offsets)
offsets
The offsets from the CFtime instance.
TRUE
.
month_days()
Determine the number of days in the month of the calendar.
CFCalendarStandard$month_days(ymd = NULL)
ymd
data.frame
, optional, with dates parsed into their parts.
A vector indicating the number of days in each month for the
dates supplied as argument ymd
. If no dates are supplied, the number
of days per month for the calendar as a vector of length 12, for a
regular year without a leap day.
leap_year()
Indicate which years are leap years.
CFCalendarStandard$leap_year(yr)
yr
Integer vector of years to test.
Logical vector with the same length as argument yr
. NA
is
returned where elements in argument yr
are NA
.
date2offset()
Calculate difference in days between a data.frame
of time
parts and the origin.
CFCalendarStandard$date2offset(x)
x
data.frame
. Dates to calculate the difference for.
Integer vector of a length equal to the number of rows in
argument x
indicating the number of days between x
and the origin
of the calendar, or NA
for rows in x
with NA
values.
offset2date()
Calculate date parts from day differences from the origin. This only deals with days as these are impacted by the calendar. Hour-minute-second timestamp parts are handled in CFCalendar.
CFCalendarStandard$offset2date(x)
x
Integer vector of days to add to the origin.
A data.frame
with columns 'year', 'month' and 'day' and as many
rows as the length of vector x
.
clone()
The objects of this class are cloneable with this method.
CFCalendarStandard$clone(deep = FALSE)
deep
Whether to make a deep clone.