Package 'aion'

Title:	Archaeological Time Series
Description:	A toolkit for archaeological time series and time intervals. This package provides a system of classes and methods to represent and work with archaeological time series and time intervals. Dates are represented as "rata die" and can be converted to (virtually) any calendar defined by Reingold and Dershowitz (2018) <doi:10.1017/9781107415058>. This packages offers a simple API that can be used by other specialized packages.
Authors:	Nicolas Frerebeau [aut, cre] , Joe Roe [aut] , Brice Lebrun [ctb] (<https://orcid.org/0000-0001-7503-8685>, Logo designer), Université Bordeaux Montaigne [fnd], CNRS [fnd]
Maintainer:	Nicolas Frerebeau <[email protected]>
License:	GPL (>= 3)
Version:	1.3.0
Built:	2024-12-10 11:19:24 UTC
Source:	https://github.com/tesselle/aion

Arithmetic Operators

Description

Operators performing arithmetic operations.

Usage

## S4 method for signature 'RataDie,RataDie'
Arith(e1, e2)

## S4 method for signature 'numeric,RataDie'
Arith(e1, e2)

## S4 method for signature 'RataDie,numeric'
Arith(e1, e2)
## S4 method for signature 'RataDie,RataDie'
Arith(e1, e2)

## S4 method for signature 'numeric,RataDie'
Arith(e1, e2)

## S4 method for signature 'RataDie,numeric'
Arith(e1, e2)

Arguments

e1, e2

A RataDie object or a numeric vector.

Details

Rata die will be converted to a plain numeric vector if a computation no longer makes sense in temporal terms.

Value

A logical vector.

Author(s)

N. Frerebeau

Examples

## Vectors of years
x <- fixed(c(-350, 31, 1072, 576, 1130), calendar = CE())
y <- fixed(c(1494, 1645, -869, 1440, 1851), calendar = CE())

## Move forward in time
x + y

## Move backward in time
x - y

## Not rata die anymore
x * y
## Vectors of years
x <- fixed(c(-350, 31, 1072, 576, 1130), calendar = CE())
y <- fixed(c(1494, 1645, -869, 1440, 1851), calendar = CE())

## Move forward in time
x + y

## Move backward in time
x - y

## Not rata die anymore
x * y

Date Conversion from Rata Die

Description

Date Conversion from Rata Die

Usage

as_date(object, calendar)

## S4 method for signature 'numeric,GregorianCalendar'
as_date(object, calendar)

## S4 method for signature 'numeric,JulianCalendar'
as_date(object, calendar)
as_date(object, calendar)

## S4 method for signature 'numeric,GregorianCalendar'
as_date(object, calendar)

## S4 method for signature 'numeric,JulianCalendar'
as_date(object, calendar)

Arguments

`object`	A `RataDie` object (see `fixed()`).
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`).

Value

A numeric vector of (decimal) years.

Author(s)

N. Frerebeau

References

Reingold, E. M. and Dershowitz, N. (2018). Calendrical Calculations: The Ultimate Edition. Cambridge University Press. doi:10.1017/9781107415058.

Examples

## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)
## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)

Converts a Date to a Decimal of its Year

Description

Converts a Date to a Decimal of its Year

Usage

as_decimal(year, month, day, calendar)

## S4 method for signature 'numeric,numeric,numeric,GregorianCalendar'
as_decimal(year, month, day, calendar)

## S4 method for signature 'numeric,numeric,numeric,JulianCalendar'
as_decimal(year, month, day, calendar)
as_decimal(year, month, day, calendar)

## S4 method for signature 'numeric,numeric,numeric,GregorianCalendar'
as_decimal(year, month, day, calendar)

## S4 method for signature 'numeric,numeric,numeric,JulianCalendar'
as_decimal(year, month, day, calendar)

Arguments

`year`	A `numeric` vector of years. If `month` and `day` are missing, decimal years are expected.
`month`	A `numeric` vector of months.
`day`	A `numeric` vector of days.
`calendar`	A `TimeScale` object specifying the calendar of `year`, `month` and `day` (see `calendar()`).

Value

A numeric vector of (ecimal years.

Author(s)

N. Frerebeau

Examples

## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)
## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)

Coerce to Rata Die

Description

Coerce to Rata Die

Usage

as_fixed(from)

## S4 method for signature 'numeric'
as_fixed(from)
as_fixed(from)

## S4 method for signature 'numeric'
as_fixed(from)

Arguments

from

A numeric vector of rata die.

Value

A RataDie object.

Author(s)

N. Frerebeau

References

Reingold, E. M. and Dershowitz, N. (2018). Calendrical Calculations: The Ultimate Edition. Cambridge University Press. doi:10.1017/9781107415058.

Examples

## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)
## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)

Year Conversion from Rata Die

Description

Year Conversion from Rata Die

Usage

as_year(object, calendar, ...)

## S4 method for signature 'numeric,GregorianCalendar'
as_year(object, calendar, decimal = TRUE, ...)

## S4 method for signature 'numeric,JulianCalendar'
as_year(object, calendar, decimal = FALSE, ...)
as_year(object, calendar, ...)

## S4 method for signature 'numeric,GregorianCalendar'
as_year(object, calendar, decimal = TRUE, ...)

## S4 method for signature 'numeric,JulianCalendar'
as_year(object, calendar, decimal = FALSE, ...)

Arguments

`object`	A `RataDie` object (see `fixed()`).
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`).
`...`	Currently not used.
`decimal`	A `logical` scalar: should decimal years be returned? If `FALSE`, the decimal part is dropped.

Value

A numeric vector of (decimal) years.

Author(s)

N. Frerebeau

References

Reingold, E. M. and Dershowitz, N. (2018). Calendrical Calculations: The Ultimate Edition. Cambridge University Press. doi:10.1017/9781107415058.

Examples

## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)
## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)

Coerce to a Data Frame

Description

Coerce to a Data Frame

Usage

## S4 method for signature 'TimeSeries'
as.data.frame(x, ..., calendar = NULL)

## S4 method for signature 'TimeIntervals'
as.data.frame(x, ..., calendar = NULL)
## S4 method for signature 'TimeSeries'
as.data.frame(x, ..., calendar = NULL)

## S4 method for signature 'TimeIntervals'
as.data.frame(x, ..., calendar = NULL)

Arguments

`x`	A `TimeSeries` or a `TimeIntervals` object.
`...`	Further parameters to be passed to `data.frame()`.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`). If `NULL` (the default), rata die are returned.

Value

A data.frame.

Methods (by class)

as.data.frame(TimeSeries): Returns a long data.frame with the following columns:

time

The (decimal) years at which the time series was sampled.

series

The name of the time series.

variable

The name of the variables.

value

The observed value.
as.data.frame(TimeIntervals): Returns a data.frame with the following columns:

label

The name of the intervals.

start

The start time of the intervals, in (decimal) years.

end

The end time of the intervals, in (decimal) years.

Author(s)

N. Frerebeau

Examples

## Create time-series of 20 observations

## Univariate
## Sampled every years starting from 1029 BCE
(X <- series(rnorm(30), time = 1029:1000, calendar = BCE()))

## Terminal and sampling times (returns rata die)
start(X)
end(X)
time(X)
span(X)

## Multivariate
## Sampled every century starting from 1000 CE
(Y <- series(matrix(rnorm(90), 30, 3), time = 1000:1029, calendar = CE()))

## Terminal and sampling times (returns Gregorian Common Era years)
start(Y, calendar = CE())
end(Y, calendar = CE())
time(Y, calendar = CE())
span(Y, calendar = CE())

## Coerce to data frame
df <- as.data.frame(Y, calendar = BP())
head(df)
## Create time-series of 20 observations

## Univariate
## Sampled every years starting from 1029 BCE
(X <- series(rnorm(30), time = 1029:1000, calendar = BCE()))

## Terminal and sampling times (returns rata die)
start(X)
end(X)
time(X)
span(X)

## Multivariate
## Sampled every century starting from 1000 CE
(Y <- series(matrix(rnorm(90), 30, 3), time = 1000:1029, calendar = CE()))

## Terminal and sampling times (returns Gregorian Common Era years)
start(Y, calendar = CE())
end(Y, calendar = CE())
time(Y, calendar = CE())
span(Y, calendar = CE())

## Coerce to data frame
df <- as.data.frame(Y, calendar = BP())
head(df)

Calendar

Description

Calendar

Usage

calendar(object)

## S4 method for signature 'character'
calendar(object)
calendar(object)

## S4 method for signature 'character'
calendar(object)

Arguments

object

A character string specifying the abbreviated label of the time scale (see details) or an object from which to extract the time scale.

Details

The following time scales are available:

label	era	calendar
`BP`	Before Present	Gregorian
`BC`	Before Christ	Gregorian
`BCE`	Before Common Era	Gregorian
`AD`	Anno Domini	Gregorian
`CE`	Common Era	Gregorian
`b2k`	Years before 2000	Gregorian
`julian`		Julian

Value

A TimeScale object.

Note

Inspired by era::era() by Joe Roe.

Author(s)

N. Frerebeau

Examples

## Define time scales
calendar("BP")
calendar("AD")
calendar("julian")

## Shortcuts
BP()
AD()
J()
## Define time scales
calendar("BP")
calendar("AD")
calendar("julian")

## Shortcuts
BP()
AD()
J()

Calendar Parameters

Description

Calendar Parameters

Usage

calendar_label(object)

calendar_name(object)

calendar_unit(object)

calendar_epoch(object)

calendar_fixed(object)

calendar_direction(object)

calendar_year(object)

## S4 method for signature 'TimeScale'
calendar_label(object)

## S4 method for signature 'TimeScale'
calendar_name(object)

## S4 method for signature 'TimeScale'
calendar_unit(object)

## S4 method for signature 'TimeScale'
calendar_epoch(object)

## S4 method for signature 'TimeScale'
calendar_fixed(object)

## S4 method for signature 'TimeScale'
calendar_direction(object)

## S4 method for signature 'NULL'
calendar_direction(object)

## S4 method for signature 'TimeScale'
calendar_year(object)
calendar_label(object)

calendar_name(object)

calendar_unit(object)

calendar_epoch(object)

calendar_fixed(object)

calendar_direction(object)

calendar_year(object)

## S4 method for signature 'TimeScale'
calendar_label(object)

## S4 method for signature 'TimeScale'
calendar_name(object)

## S4 method for signature 'TimeScale'
calendar_unit(object)

## S4 method for signature 'TimeScale'
calendar_epoch(object)

## S4 method for signature 'TimeScale'
calendar_fixed(object)

## S4 method for signature 'TimeScale'
calendar_direction(object)

## S4 method for signature 'NULL'
calendar_direction(object)

## S4 method for signature 'TimeScale'
calendar_year(object)

Arguments

object

A TimeScale object.

Value

calendar_label() returns a character string giving the abbreviated label of the time scale.
calendar_name() returns a character string giving the name of the time scale.
calendar_unit() returns a character string giving the unit of the calendar.
calendar_fixed() returns a length-one numeric vector giving the reference date of the calendar (in rata die).
calendar_epoch() returns a length-one numeric vector giving the epoch year from which years are counted (starting date of the calendar, in years).
calendar_direction() returns a length-one integer vector specifying if years are counted backwards ( $-1$ ) or forwards ( $1$ ) from epoch. Only the sign of calendar_direction() is relevant.
calendar_year() returns a length-one numeric vector giving the average length of the year in solar days.

Author(s)

N. Frerebeau

Examples

## Define time scales
calendar("BP")
calendar("AD")
calendar("julian")

## Shortcuts
BP()
AD()
J()
## Define time scales
calendar("BP")
calendar("AD")
calendar("julian")

## Shortcuts
BP()
AD()
J()

Calendar Converter

Description

Interconverts dates in a variety of calendars.

Usage

convert(from, to, ...)

## S4 method for signature 'character,character'
convert(from, to)

## S4 method for signature 'TimeScale,TimeScale'
convert(from, to)
convert(from, to, ...)

## S4 method for signature 'character,character'
convert(from, to)

## S4 method for signature 'TimeScale,TimeScale'
convert(from, to)

Arguments

`from`	A `TimeScale` object describing the source calendar.
`to`	A `TimeScale` object describing the target calendar.
`...`	Currently not used.

Value

A function that when called with a single numeric argument (factional years) converts years from one calendar to another.

Author(s)

N. Frerebeau

Examples

## Define time scales
BP <- calendar("BP")
AD <- calendar("AD")

## Make conversion functions
BP_to_AD <- convert(BP, AD)
AD_to_BP <- convert(AD, BP)

## Convert years
BP_to_AD(0)
AD_to_BP(1950)
## Define time scales
BP <- calendar("BP")
AD <- calendar("AD")

## Make conversion functions
BP_to_AD <- convert(BP, AD)
AD_to_BP <- convert(AD, BP)

## Convert years
BP_to_AD(0)
AD_to_BP(1950)

Sample Data from Reingold and Dershowitz (2018)

Description

A dataset of 33 dates from the years -1000 to 2100 with their equivalents on differents calendars.

Usage

dates
dates

Format

A data.frame with 33 rows and 14 variables:

rata_die: Rata die.
weekday: Week day.
jd: Julian day.
mjd: Modified Julian day.
unix: Unix.
gregorian_year, gregorian_month, gregorian_day: Gregorian date.
julian_year, julian_month, julian_day: Julian date.
egyptian_year, egyptian_month, egyptian_day: Egyptian date.

References

Reingold, E. M. and Dershowitz, N. (2018). Calendrical Calculations: The Ultimate Edition. Cambridge University Press. doi:10.1017/9781107415058.

Rata Die (Fixed Date)

Description

Rata Die (Fixed Date)

Usage

fixed(year, month, day, calendar, ...)

## S4 method for signature 'numeric,missing,missing,GregorianCalendar'
fixed(year, calendar, scale = 1)

## S4 method for signature 'numeric,numeric,numeric,GregorianCalendar'
fixed(year, month, day, calendar)

## S4 method for signature 'numeric,missing,missing,JulianCalendar'
fixed(year, calendar, scale = 1)

## S4 method for signature 'numeric,numeric,numeric,JulianCalendar'
fixed(year, month, day, calendar)
fixed(year, month, day, calendar, ...)

## S4 method for signature 'numeric,missing,missing,GregorianCalendar'
fixed(year, calendar, scale = 1)

## S4 method for signature 'numeric,numeric,numeric,GregorianCalendar'
fixed(year, month, day, calendar)

## S4 method for signature 'numeric,missing,missing,JulianCalendar'
fixed(year, calendar, scale = 1)

## S4 method for signature 'numeric,numeric,numeric,JulianCalendar'
fixed(year, month, day, calendar)

Arguments

`year`	A `numeric` vector of years. If `month` and `day` are missing, decimal years are expected.
`month`	A `numeric` vector of months.
`day`	A `numeric` vector of days.
`calendar`	A `TimeScale` object specifying the calendar of `year`, `month` and `day` (see `calendar()`).
`...`	Currently not used.
`scale`	A length-one `integer` vector specifying the number of years represented by one unit. It should be a power of 10 (i.e. 1000 means ka).

Details

Rata die are represented as the number of days since 01-01-01 (Gregorian), with negative values for earlier dates.

Value

A RataDie object.

Author(s)

N. Frerebeau

References

Reingold, E. M. and Dershowitz, N. (2018). Calendrical Calculations: The Ultimate Edition. Cambridge University Press. doi:10.1017/9781107415058.

Examples

## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)
## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)

Rata Die Conversion to and from Gregorian Years

Description

Convenient functions for conversion from and to rata die for a given Gregorian era.

Usage

fixed_from_BP(year, month, day)

fixed_to_BP(object)

fixed_from_BC(year, month, day)

fixed_to_BC(object)

fixed_from_BCE(year, month, day)

fixed_to_BCE(object)

fixed_from_AD(year, month, day)

fixed_to_AD(object)

fixed_from_CE(year, month, day)

fixed_to_CE(object)

fixed_from_b2k(year, month, day)

fixed_to_b2k(object)
fixed_from_BP(year, month, day)

fixed_to_BP(object)

fixed_from_BC(year, month, day)

fixed_to_BC(object)

fixed_from_BCE(year, month, day)

fixed_to_BCE(object)

fixed_from_AD(year, month, day)

fixed_to_AD(object)

fixed_from_CE(year, month, day)

fixed_to_CE(object)

fixed_from_b2k(year, month, day)

fixed_to_b2k(object)

Arguments

`year`	A `numeric` vector of years. If `month` and `day` are missing, decimal years are expected.
`month`	A `numeric` vector of months.
`day`	A `numeric` vector of days.
`object`	A `RataDie` object (see `fixed()`).

Details

The astronomical notation is used for Gregorian years (there is a year 0).

Value

⁠fixed_from_*()⁠ returns a RataDie object.
⁠fixed_to_*()⁠ returns a numeric vector of Gregorian years.

Author(s)

N. Frerebeau

References

Reingold, E. M. and Dershowitz, N. (2018). Calendrical Calculations: The Ultimate Edition. Cambridge University Press. doi:10.1017/9781107415058.

Examples

## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)
## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)

Rata Die Conversion to and from Julian Years

Description

Convenient functions for conversion from and to rata die.

Usage

fixed_from_julian(year, month, day)

fixed_to_julian(object)
fixed_from_julian(year, month, day)

fixed_to_julian(object)

Arguments

`year`	A `numeric` vector of years. If `month` and `day` are missing, decimal years are expected.
`month`	A `numeric` vector of months.
`day`	A `numeric` vector of days.
`object`	A `RataDie` object (see `fixed()`).

Value

fixed_from_julian() returns a RataDie object.
fixed_to_julian() returns a numeric vector of Julian years.

Author(s)

N. Frerebeau

References

Reingold, E. M. and Dershowitz, N. (2018). Calendrical Calculations: The Ultimate Edition. Cambridge University Press. doi:10.1017/9781107415058.

Examples

## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)
## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)

Date Conversion to Character

Description

Date Conversion to Character

Usage

## S4 method for signature 'TimeScale'
format(x, ...)

## S4 method for signature 'RataDie'
format(
  x,
  prefix = c("a", "ka", "Ma", "Ga"),
  label = TRUE,
  calendar = getOption("aion.calendar"),
  ...
)
## S4 method for signature 'TimeScale'
format(x, ...)

## S4 method for signature 'RataDie'
format(
  x,
  prefix = c("a", "ka", "Ma", "Ga"),
  label = TRUE,
  calendar = getOption("aion.calendar"),
  ...
)

Arguments

`x`	A `RataDie` object.
`...`	Currently not used.
`prefix`	A `character` string specifying the prefix. It should be one of "`a`", "`ka`", "`Ma`" or "`Ga`". If `TRUE`, a good guess for an appropriate format is made.
`label`	A `logical` scalar: should the label of the calendar be displayed?
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`).

Value

A character vector representing the date.

Author(s)

N. Frerebeau

Examples

## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)
## R 1.0.0
(y <- fixed(year = 2000, month = 02, day = 29, calendar = CE()))
as_date(y, calendar = CE())
as_year(y, calendar = CE())

## Create a vector of years BP (Gregorian)
## (every two years starting from 2000 BP)
(years <- seq(from = 2000, by = -2, length.out = 10))
## Convert years to rata die
(rd <- fixed(years, calendar = BP()))
## Convert back to Gregorian years BP
as_year(rd, calendar = BP())

## More convenient
(rd <- fixed_from_BP(years))
fixed_to_BP(rd)

Gregorian Calendar

Description

Gregorian Calendar

Usage

BP(...)

b2k(...)

BC(...)

BCE(...)

AD(...)

CE(...)
BP(...)

b2k(...)

BC(...)

BCE(...)

AD(...)

CE(...)

Arguments

...

Currently not used.

Value

A GregorianCalendar object.

Author(s)

N. Frerebeau

Examples

## Define time scales
calendar("BP")
calendar("AD")
calendar("julian")

## Shortcuts
BP()
AD()
J()
## Define time scales
calendar("BP")
calendar("AD")
calendar("julian")

## Shortcuts
BP()
AD()
J()

Heat Map

Description

Heat Map

Usage

## S4 method for signature 'TimeSeries'
image(x, calendar = getOption("aion.calendar"), k = 1, ...)
## S4 method for signature 'TimeSeries'
image(x, calendar = getOption("aion.calendar"), k = 1, ...)

Arguments

`x`	A `TimeSeries` object.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`).
`k`	An `integer` specifying the slice of `x` along the third dimension to be plotted.
`...`	Further parameters to be passed to `graphics::image()`.

Value

image() is called for its side-effects: it results in a graphic being displayed. Invisibly returns x.

Author(s)

N. Frerebeau

Examples

## Create 6 time-series of 50 observations
## Sampled every two years starting from 2000 BP
X <- series(
  object = matrix(rnorm(300), nrow = 50, ncol = 6),
  time = seq(2000, by = -2, length.out = 50),
  calendar = BP()
)

## Image
image(X, calendar = CE())
## Create 6 time-series of 50 observations
## Sampled every two years starting from 2000 BP
X <- series(
  object = matrix(rnorm(300), nrow = 50, ncol = 6),
  time = seq(2000, by = -2, length.out = 50),
  calendar = BP()
)

## Image
image(X, calendar = CE())

Create Time Intervals

Description

An Interval is elapsed time in seconds between two specific years.

Usage

intervals(start, end, calendar, ...)

## S4 method for signature 'RataDie,RataDie,missing'
intervals(start, end, names = NULL)

## S4 method for signature 'numeric,numeric,TimeScale'
intervals(start, end, calendar, scale = 1, names = NULL)
intervals(start, end, calendar, ...)

## S4 method for signature 'RataDie,RataDie,missing'
intervals(start, end, names = NULL)

## S4 method for signature 'numeric,numeric,TimeScale'
intervals(start, end, calendar, scale = 1, names = NULL)

Arguments

`start`	A `numeric` vector of (decimal) years or a `RataDie` object (see `fixed()`) giving the beginning of the time intervals.
`end`	A `numeric` vector of (decimal) years or a `RataDie` object (see `fixed()`) giving the end of the time intervals.
`calendar`	A `TimeScale` object specifying the calendar of `time` (see `calendar()`). If missing, `time` must be a `RataDie` object.
`...`	Currently not used.
`names`	A `character` string specifying the names of the time series.
`scale`	A length-one `numeric` vector specifying the number of years represented by one unit. It should be a power of 10 (i.e. 1000 means ka).

Value

A TimeIntervals object.

Author(s)

N. Frerebeau

Examples

## Create time intervals
int <- intervals(
  start = c(625, 700, 1200, 1225, 1250, 500, 1000, 1200,
            1325, 1375, 1200, 1300, 1375, 1275, 1325),
  end = c(750, 825, 1250, 1275, 1325, 700, 1300, 1325,
          1400, 1500, 1300, 1375, 1500, 1325, 1425),
  calendar = CE()
)

## Plot intervals
plot(int) # Default calendar

## Overlap
overlap(int, calendar = CE())
## Create time intervals
int <- intervals(
  start = c(625, 700, 1200, 1225, 1250, 500, 1000, 1200,
            1325, 1375, 1200, 1300, 1375, 1275, 1325),
  end = c(750, 825, 1250, 1275, 1325, 700, 1300, 1325,
          1400, 1500, 1300, 1375, 1500, 1325, 1425),
  calendar = CE()
)

## Plot intervals
plot(int) # Default calendar

## Overlap
overlap(int, calendar = CE())

Is an Object a Calendar?

Description

Test inheritance relationships between an object and a calendar class.

Usage

is_gregorian(object)

is_julian(object)

## S4 method for signature 'ANY'
is_gregorian(object)

## S4 method for signature 'ANY'
is_julian(object)
is_gregorian(object)

is_julian(object)

## S4 method for signature 'ANY'
is_gregorian(object)

## S4 method for signature 'ANY'
is_julian(object)

Arguments

object

Any R object.

Value

A logical vector.

Author(s)

N. Frerebeau

Julian Calendar

Description

Julian Calendar

Usage

J(...)
J(...)

Arguments

...

Currently not used.

Value

A JulianCalendar object.

Author(s)

N. Frerebeau

Examples

## Define time scales
calendar("BP")
calendar("AD")
calendar("julian")

## Shortcuts
BP()
AD()
J()
## Define time scales
calendar("BP")
calendar("AD")
calendar("julian")

## Shortcuts
BP()
AD()
J()

Length

Description

Get the length of an object.

Usage

## S4 method for signature 'TimeIntervals'
length(x)
## S4 method for signature 'TimeIntervals'
length(x)

Arguments

`x`	An R object.

Value

A length-one integer vector.

Author(s)

N. Frerebeau

Time Overlap

Description

Computes the length of overlap of time intervals.

Usage

overlap(x, ...)

## S4 method for signature 'TimeIntervals'
overlap(x, calendar = NULL)
overlap(x, ...)

## S4 method for signature 'TimeIntervals'
overlap(x, calendar = NULL)

Arguments

`x`	A `TimeIntervals` object.
`...`	Currently not used.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`). If `NULL` (the default), rata die are returned.

Details

The overlap of two time intervals is a difference between the minimum value of the two upper boundaries and the maximum value of the two lower boundaries, plus 1.

Value

A symmetric numeric matrix of years.

Author(s)

N. Frerebeau

Examples

## Create time intervals
int <- intervals(
  start = c(625, 700, 1200, 1225, 1250, 500, 1000, 1200,
            1325, 1375, 1200, 1300, 1375, 1275, 1325),
  end = c(750, 825, 1250, 1275, 1325, 700, 1300, 1325,
          1400, 1500, 1300, 1375, 1500, 1325, 1425),
  calendar = CE()
)

## Plot intervals
plot(int) # Default calendar

## Overlap
overlap(int, calendar = CE())
## Create time intervals
int <- intervals(
  start = c(625, 700, 1200, 1225, 1250, 500, 1000, 1200,
            1325, 1375, 1200, 1300, 1375, 1275, 1325),
  end = c(750, 825, 1250, 1275, 1325, 700, 1300, 1325,
          1400, 1500, 1300, 1375, 1500, 1325, 1425),
  calendar = CE()
)

## Plot intervals
plot(int) # Default calendar

## Overlap
overlap(int, calendar = CE())

Plot Time Series and Time Intervals

Description

Plot Time Series and Time Intervals

Usage

## S4 method for signature 'TimeIntervals,missing'
plot(
  x,
  calendar = getOption("aion.calendar"),
  sort = TRUE,
  decreasing = FALSE,
  xlab = NULL,
  ylab = NULL,
  main = NULL,
  sub = NULL,
  ann = graphics::par("ann"),
  axes = TRUE,
  frame.plot = axes,
  panel.first = NULL,
  panel.last = NULL,
  ...
)

## S4 method for signature 'TimeSeries,missing'
plot(
  x,
  facet = c("multiple", "single"),
  calendar = getOption("aion.calendar"),
  panel = graphics::lines,
  flip = FALSE,
  ncol = NULL,
  xlab = NULL,
  ylab = NULL,
  main = NULL,
  sub = NULL,
  ann = graphics::par("ann"),
  axes = TRUE,
  frame.plot = axes,
  panel.first = NULL,
  panel.last = NULL,
  ...
)
## S4 method for signature 'TimeIntervals,missing'
plot(
  x,
  calendar = getOption("aion.calendar"),
  sort = TRUE,
  decreasing = FALSE,
  xlab = NULL,
  ylab = NULL,
  main = NULL,
  sub = NULL,
  ann = graphics::par("ann"),
  axes = TRUE,
  frame.plot = axes,
  panel.first = NULL,
  panel.last = NULL,
  ...
)

## S4 method for signature 'TimeSeries,missing'
plot(
  x,
  facet = c("multiple", "single"),
  calendar = getOption("aion.calendar"),
  panel = graphics::lines,
  flip = FALSE,
  ncol = NULL,
  xlab = NULL,
  ylab = NULL,
  main = NULL,
  sub = NULL,
  ann = graphics::par("ann"),
  axes = TRUE,
  frame.plot = axes,
  panel.first = NULL,
  panel.last = NULL,
  ...
)

Arguments

`x`	A `TimeSeries` or a `TimeIntervals` object.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`).
`sort`	A `logical` scalar: should the data be sorted in chronological order?
`decreasing`	A `logical` scalar: should the sort order be decreasing? Only used if `sort` is `TRUE`.
`xlab`, `ylab`	A `character` vector giving the x and y axis labels.
`main`	A `character` string giving a main title for the plot.
`sub`	A `character` string giving a subtitle for the plot.
`ann`	A `logical` scalar: should the default annotation (title and x and y axis labels) appear on the plot?
`axes`	A `logical` scalar: should axes be drawn on the plot?
`frame.plot`	A `logical` scalar: should a box be drawn around the plot?
`panel.first`	An `expression` to be evaluated after the plot axes are set up but before any plotting takes place. This can be useful for drawing background grids.
`panel.last`	An `expression` to be evaluated after plotting has taken place but before the axes, title and box are added.
`...`	Further parameters to be passed to `panel` (e.g. graphical parameters).
`facet`	A `character` string specifying whether the series should be plotted separately (with a common time axis) or on a single plot? It must be one of "`multiple`" or "`single`". Any unambiguous substring can be given.
`panel`	A `function` in the form `⁠function(x, y, ...)⁠` which gives the action to be carried out in each panel of the display. The default is `graphics::lines()`.
`flip`	A `logical` scalar: should the y-axis (ticks and numbering) be flipped from side 2 (left) to 4 (right) from series to series when `facet` is "`multiple`"?
`ncol`	An `integer` specifying the number of columns to use when `facet` is "`multiple`". Defaults to 1 for up to 4 series, otherwise to 2.

Value

plot() is called for its side-effects: it results in a graphic being displayed. Invisibly returns x.

Author(s)

N. Frerebeau

Examples

## Create 6 time-series of 50 observations
## Sampled every two years starting from 2000 BP
X <- series(
  object = matrix(rnorm(300), nrow = 50, ncol = 6),
  time = seq(2000, by = -2, length.out = 50),
  calendar = BP()
)

## Multiple
plot(X) # Default calendar
plot(X, calendar = BP(), flip = TRUE) # BP
plot(X, calendar = b2k(), ncol = 1) # b2k

## Single
plot(X, facet = "single") # CE
plot(X, facet = "single", calendar = BP()) # BP

## Create 6 x 3 time-series of 50 observations
## Sampled every two years starting from 2000 BP
X <- series(
  object = array(rnorm(900), dim = c(50, 6, 3)),
  time = seq(2000, by = 2, length.out = 50),
  calendar = BP()
)
plot(X, calendar = BP(), flip = TRUE) # BP
plot(X, calendar = b2k(), ncol = 1) # b2k

## Graphical parameters
plot(X, lwd = c(1, 2, 3), col = c("#004488", "#DDAA33", "#BB5566"))
plot(X, type = "b", pch = 16, col = c("#004488", "#DDAA33", "#BB5566"))
plot(X, type = "p", pch = c(16, 17, 18), cex = c(1, 2, 3))
## Create 6 time-series of 50 observations
## Sampled every two years starting from 2000 BP
X <- series(
  object = matrix(rnorm(300), nrow = 50, ncol = 6),
  time = seq(2000, by = -2, length.out = 50),
  calendar = BP()
)

## Multiple
plot(X) # Default calendar
plot(X, calendar = BP(), flip = TRUE) # BP
plot(X, calendar = b2k(), ncol = 1) # b2k

## Single
plot(X, facet = "single") # CE
plot(X, facet = "single", calendar = BP()) # BP

## Create 6 x 3 time-series of 50 observations
## Sampled every two years starting from 2000 BP
X <- series(
  object = array(rnorm(900), dim = c(50, 6, 3)),
  time = seq(2000, by = 2, length.out = 50),
  calendar = BP()
)
plot(X, calendar = BP(), flip = TRUE) # BP
plot(X, calendar = b2k(), ncol = 1) # b2k

## Graphical parameters
plot(X, lwd = c(1, 2, 3), col = c("#004488", "#DDAA33", "#BB5566"))
plot(X, type = "b", pch = 16, col = c("#004488", "#DDAA33", "#BB5566"))
plot(X, type = "p", pch = c(16, 17, 18), cex = c(1, 2, 3))

Pretty Breakpoints

Description

Pretty Breakpoints

Usage

## S4 method for signature 'RataDie'
pretty(x, calendar = getOption("aion.calendar"), ...)
## S4 method for signature 'RataDie'
pretty(x, calendar = getOption("aion.calendar"), ...)

Arguments

`x`	A `RataDie` object.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`).
`...`	Further parameters to be passed to `base::pretty()`.

Details

pretty() computes a vector of increasing numbers which are "pretty" in decimal notation of calendar. Pretty breakpoints are then converted to rata die.

Value

A RataDie object.

RataDie

Description

An S4 class to represent a vector of rata die.

Details

Rata die (fixed date) are represented as the number of days since 01-01-01 (Gregorian), with negative values for earlier dates.

It is intended that the date should be an integer value, but this is not enforced in the internal representation.

Slots

.Data: A numeric vector giving the rata die values.

Note

This class inherits from numeric.

Author(s)

N. Frerebeau

Create Time Series

Description

Create Time Series

Usage

series(object, time, calendar, ...)

## S4 method for signature 'array,RataDie,missing'
series(object, time, names = NULL)

## S4 method for signature 'array,numeric,TimeScale'
series(object, time, calendar, scale = 1, names = NULL)

## S4 method for signature 'matrix,numeric,TimeScale'
series(object, time, calendar, scale = 1, names = NULL)

## S4 method for signature 'matrix,RataDie,missing'
series(object, time, names = NULL)

## S4 method for signature 'numeric,numeric,TimeScale'
series(object, time, calendar, scale = 1, names = NULL)

## S4 method for signature 'numeric,RataDie,missing'
series(object, time, names = NULL)

## S4 method for signature 'data.frame,numeric,TimeScale'
series(object, time, calendar, scale = 1, names = NULL)

## S4 method for signature 'data.frame,RataDie,missing'
series(object, time, names = NULL)
series(object, time, calendar, ...)

## S4 method for signature 'array,RataDie,missing'
series(object, time, names = NULL)

## S4 method for signature 'array,numeric,TimeScale'
series(object, time, calendar, scale = 1, names = NULL)

## S4 method for signature 'matrix,numeric,TimeScale'
series(object, time, calendar, scale = 1, names = NULL)

## S4 method for signature 'matrix,RataDie,missing'
series(object, time, names = NULL)

## S4 method for signature 'numeric,numeric,TimeScale'
series(object, time, calendar, scale = 1, names = NULL)

## S4 method for signature 'numeric,RataDie,missing'
series(object, time, names = NULL)

## S4 method for signature 'data.frame,numeric,TimeScale'
series(object, time, calendar, scale = 1, names = NULL)

## S4 method for signature 'data.frame,RataDie,missing'
series(object, time, names = NULL)

Arguments

`object`	A `numeric` `vector`, `matrix` or `array` of the observed time-series values. A `data.frame` will be coerced to a `numeric` `matrix` via `data.matrix()`.
`time`	A `numeric` vector of (decimal) years or a `RataDie` object (see `fixed()`).
`calendar`	A `TimeScale` object specifying the calendar of `time` (see `calendar()`). If missing, `time` must be a `RataDie` object.
`...`	Currently not used.
`names`	A `character` string specifying the names of the time series.
`scale`	A length-one `numeric` vector specifying the number of years represented by one unit. It should be a power of 10 (i.e. 1000 means ka).

Details

Data will be sorted in chronological order.

Value

A TimeSeries object.

Author(s)

N. Frerebeau

Examples

## Create time-series of 20 observations

## Univariate
## Sampled every years starting from 1029 BCE
(X <- series(rnorm(30), time = 1029:1000, calendar = BCE()))

## Terminal and sampling times (returns rata die)
start(X)
end(X)
time(X)
span(X)

## Multivariate
## Sampled every century starting from 1000 CE
(Y <- series(matrix(rnorm(90), 30, 3), time = 1000:1029, calendar = CE()))

## Terminal and sampling times (returns Gregorian Common Era years)
start(Y, calendar = CE())
end(Y, calendar = CE())
time(Y, calendar = CE())
span(Y, calendar = CE())

## Coerce to data frame
df <- as.data.frame(Y, calendar = BP())
head(df)
## Create time-series of 20 observations

## Univariate
## Sampled every years starting from 1029 BCE
(X <- series(rnorm(30), time = 1029:1000, calendar = BCE()))

## Terminal and sampling times (returns rata die)
start(X)
end(X)
time(X)
span(X)

## Multivariate
## Sampled every century starting from 1000 CE
(Y <- series(matrix(rnorm(90), 30, 3), time = 1000:1029, calendar = CE()))

## Terminal and sampling times (returns Gregorian Common Era years)
start(Y, calendar = CE())
end(Y, calendar = CE())
time(Y, calendar = CE())
span(Y, calendar = CE())

## Coerce to data frame
df <- as.data.frame(Y, calendar = BP())
head(df)

Duration

Description

Get the duration of time series or intervals.

Usage

span(x, ...)

## S4 method for signature 'TimeSeries'
span(x, calendar = NULL)

## S4 method for signature 'TimeIntervals'
span(x, calendar = NULL)
span(x, ...)

## S4 method for signature 'TimeSeries'
span(x, calendar = NULL)

## S4 method for signature 'TimeIntervals'
span(x, calendar = NULL)

Arguments

`x`	A `TimeSeries` or a `TimeIntervals` object.
`...`	Currently not used.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`). If `NULL` (the default), rata die are returned.

Value

A numeric vector of years.

Author(s)

N. Frerebeau

Examples

## Create time intervals
int <- intervals(
  start = c(625, 700, 1200, 1225, 1250, 500, 1000, 1200,
            1325, 1375, 1200, 1300, 1375, 1275, 1325),
  end = c(750, 825, 1250, 1275, 1325, 700, 1300, 1325,
          1400, 1500, 1300, 1375, 1500, 1325, 1425),
  calendar = CE()
)

## Get time durations
span(int, calendar = CE())
## Create time intervals
int <- intervals(
  start = c(625, 700, 1200, 1225, 1250, 500, 1000, 1200,
            1325, 1375, 1200, 1300, 1375, 1275, 1325),
  end = c(750, 825, 1250, 1275, 1325, 700, 1300, 1325,
          1400, 1500, 1300, 1375, 1500, 1325, 1425),
  calendar = CE()
)

## Get time durations
span(int, calendar = CE())

Terminal Times

Description

Get the times the first and last observations were taken.

Usage

## S4 method for signature 'TimeSeries'
start(x, calendar = NULL, ...)

## S4 method for signature 'TimeIntervals'
start(x, calendar = NULL, ...)

## S4 method for signature 'TimeSeries'
end(x, calendar = NULL, ...)

## S4 method for signature 'TimeIntervals'
end(x, calendar = NULL, ...)
## S4 method for signature 'TimeSeries'
start(x, calendar = NULL, ...)

## S4 method for signature 'TimeIntervals'
start(x, calendar = NULL, ...)

## S4 method for signature 'TimeSeries'
end(x, calendar = NULL, ...)

## S4 method for signature 'TimeIntervals'
end(x, calendar = NULL, ...)

Arguments

`x`	A `TimeSeries` object.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`). If `NULL` (the default), rata die are returned.
`...`	Currently not used.

Value

A numeric vector of decimal years (if calendar is not NULL).

Author(s)

N. Frerebeau

Examples

## Create time-series of 20 observations

## Univariate
## Sampled every years starting from 1029 BCE
(X <- series(rnorm(30), time = 1029:1000, calendar = BCE()))

## Terminal and sampling times (returns rata die)
start(X)
end(X)
time(X)
span(X)

## Multivariate
## Sampled every century starting from 1000 CE
(Y <- series(matrix(rnorm(90), 30, 3), time = 1000:1029, calendar = CE()))

## Terminal and sampling times (returns Gregorian Common Era years)
start(Y, calendar = CE())
end(Y, calendar = CE())
time(Y, calendar = CE())
span(Y, calendar = CE())

## Coerce to data frame
df <- as.data.frame(Y, calendar = BP())
head(df)
## Create time-series of 20 observations

## Univariate
## Sampled every years starting from 1029 BCE
(X <- series(rnorm(30), time = 1029:1000, calendar = BCE()))

## Terminal and sampling times (returns rata die)
start(X)
end(X)
time(X)
span(X)

## Multivariate
## Sampled every century starting from 1000 CE
(Y <- series(matrix(rnorm(90), 30, 3), time = 1000:1029, calendar = CE()))

## Terminal and sampling times (returns Gregorian Common Era years)
start(Y, calendar = CE())
end(Y, calendar = CE())
time(Y, calendar = CE())
span(Y, calendar = CE())

## Coerce to data frame
df <- as.data.frame(Y, calendar = BP())
head(df)

Extract or Replace Parts of an Object

Description

Operators acting on objects to extract or replace parts.

Usage

## S4 method for signature 'RataDie'
x[i]

## S4 method for signature 'TimeIntervals'
x[i]

## S4 method for signature 'TimeSeries'
x[i, j, k, drop = FALSE]
## S4 method for signature 'RataDie'
x[i]

## S4 method for signature 'TimeIntervals'
x[i]

## S4 method for signature 'TimeSeries'
x[i, j, k, drop = FALSE]

Arguments

`x`	An object from which to extract element(s) or in which to replace element(s).
`i`, `j`, `k`	Indices specifying elements to extract or replace.
`drop`	A `logical` scalar: should the result be coerced to the lowest possible dimension? This only works for extracting elements, not for the replacement.

Value

A subsetted object.

Author(s)

N. Frerebeau

Sampling Times

Description

Get the sampling times:

time() creates the vector of times at which a time series was sampled.
frequency() returns the mean number of samples per unit time.

Usage

## S4 method for signature 'TimeSeries'
time(x, calendar = NULL, ...)

## S4 method for signature 'TimeSeries'
frequency(x, ...)
## S4 method for signature 'TimeSeries'
time(x, calendar = NULL, ...)

## S4 method for signature 'TimeSeries'
frequency(x, ...)

Arguments

`x`	A `TimeSeries` object.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`). If `NULL` (the default), rata die are returned.
`...`	Currently not used.

Value

A numeric vector of decimal years (if calendar is not NULL).

Author(s)

N. Frerebeau

Examples

## Create time-series of 20 observations

## Univariate
## Sampled every years starting from 1029 BCE
(X <- series(rnorm(30), time = 1029:1000, calendar = BCE()))

## Terminal and sampling times (returns rata die)
start(X)
end(X)
time(X)
span(X)

## Multivariate
## Sampled every century starting from 1000 CE
(Y <- series(matrix(rnorm(90), 30, 3), time = 1000:1029, calendar = CE()))

## Terminal and sampling times (returns Gregorian Common Era years)
start(Y, calendar = CE())
end(Y, calendar = CE())
time(Y, calendar = CE())
span(Y, calendar = CE())

## Coerce to data frame
df <- as.data.frame(Y, calendar = BP())
head(df)
## Create time-series of 20 observations

## Univariate
## Sampled every years starting from 1029 BCE
(X <- series(rnorm(30), time = 1029:1000, calendar = BCE()))

## Terminal and sampling times (returns rata die)
start(X)
end(X)
time(X)
span(X)

## Multivariate
## Sampled every century starting from 1000 CE
(Y <- series(matrix(rnorm(90), 30, 3), time = 1000:1029, calendar = CE()))

## Terminal and sampling times (returns Gregorian Common Era years)
start(Y, calendar = CE())
end(Y, calendar = CE())
time(Y, calendar = CE())
span(Y, calendar = CE())

## Coerce to data frame
df <- as.data.frame(Y, calendar = BP())
head(df)

TimeIntervals

Description

An S4 class to represent time intervals.

Slots

.Id: A character vector specifying the identifier/name of intervals. Duplicated values are interpreted as disjoint intervals referring to the same event.
.Start: A RataDie object giving the start time of the intervals.
.End: A RataDie object giving the end time of the intervals.

Author(s)

N. Frerebeau

TimeScale

Description

A virtual S4 class to represent a calendar.

Slots

label: A character string specifying the abbreviated label of the time scale.
name: A character string specifying the name of the time scale.
epoch: A numeric value specifying the epoch year from which years are counted (starting date of the calendar, in years). Allows to define multiple era of a calendar.
fixed: A numeric value specifying the reference date of the calendar (in rata die).
direction: An integer specifying if years are counted backwards (-1) or forwards (1) from epoch.
year: A numeric value giving the average length of the year in solar days.

Author(s)

N. Frerebeau

A time series object is an $n x m x p$ array, with $n$ being the number of observations, $m$ being the number of series and with the $p$ columns of the third dimension containing extra variables for each series.

Slots

.Data: A $n x m x p$ numeric array giving the observed time-series values.
.Time: A length- $n$ RataDie object.

Note

This class inherits from array.

Author(s)

N. Frerebeau

Time Windows

Description

Extracts the subset of the object x observed between the times start and end (expressed in rata die).

Usage

## S4 method for signature 'TimeSeries'
window(x, start = NULL, end = NULL, ...)
## S4 method for signature 'TimeSeries'
window(x, start = NULL, end = NULL, ...)

Arguments

`x`	A `TimeSeries` object.
`start`	A length-one `numeric` vector specifying the start time of the period of interest.
`end`	A length-one `numeric` vector specifying the end time of the period of interest.
`...`	Currently not used.

Value

A TimeSeries object.

Author(s)

N. Frerebeau

Examples

## Create 3 time-series of 100 observations
## Sampled every years starting from 1000 CE
(x <- series(matrix(rnorm(300), 100, 3), time = 1000:1099, calendar = CE()))

## Subset between 1025 and 1050 CE
(y <- window(x, start = 374009, end = 383140))
## Create 3 time-series of 100 observations
## Sampled every years starting from 1000 CE
(x <- series(matrix(rnorm(300), 100, 3), time = 1000:1099, calendar = CE()))

## Subset between 1025 and 1050 CE
(y <- window(x, start = 374009, end = 383140))

Time Series Plotting Functions

Description

Time Series Plotting Functions

Usage

year_axis(
  side,
  at = NULL,
  format = c("a", "ka", "Ma", "Ga"),
  labels = TRUE,
  calendar = getOption("aion.last_calendar"),
  current_calendar = getOption("aion.last_calendar"),
  ...
)
year_axis(
  side,
  at = NULL,
  format = c("a", "ka", "Ma", "Ga"),
  labels = TRUE,
  calendar = getOption("aion.last_calendar"),
  current_calendar = getOption("aion.last_calendar"),
  ...
)

Arguments

`side`	An `integer` specifying which side of the plot the axis is to be drawn on. The axis is placed as follows: 1=below, 2=left, 3=above and 4=right.
`at`	A `numeric` vector giving the points at which tick-marks are to be drawn. If `NULL`, tickmark locations are computed.
`format`	A `character` string specifying the prefix. It should be one of "`a`", "`ka`", "`Ma`" or "`Ga`". If `TRUE`, a good guess for an appropriate format is made.
`labels`	A `logical` scalar specifying whether annotations are to be made at the tickmarks, or a vector of `character` strings to be placed at the tickpoints.
`calendar`	A `TimeScale` object specifying the target calendar (see `calendar()`).
`current_calendar`	A `TimeScale` object specifying the calendar used by the last call to `plot()`.
`...`	Further parameters to be passed to `graphics::axis()`. (e.g. graphical parameters).

Value

year_axis() is called it for its side-effects.

Author(s)

N. Frerebeau

Examples

## Create a time-series of 300 observations
## Sampled every two years starting from 2000 BP
X <- series(
  object = rnorm(300),
  time = seq(2000, by = -2, length.out = 300),
  calendar = BP()
)

## Axis
plot(X, axes = FALSE, calendar = BP()) # Remove axes
year_axis(side = 1) # Same calendar as last plot
year_axis(side = 3, calendar = CE()) # Specific calendar
mtext(format(CE()), side = 3, line = 3)

## Grid
plot(X, panel.first = graphics::grid())
## Create a time-series of 300 observations
## Sampled every two years starting from 2000 BP
X <- series(
  object = rnorm(300),
  time = seq(2000, by = -2, length.out = 300),
  calendar = BP()
)

## Axis
plot(X, axes = FALSE, calendar = BP()) # Remove axes
year_axis(side = 1) # Same calendar as last plot
year_axis(side = 3, calendar = CE()) # Specific calendar
mtext(format(CE()), side = 3, line = 3)

## Grid
plot(X, panel.first = graphics::grid())

Package 'aion'

Help Index

Arithmetic Operators

Description

Usage

Arguments

Details

Value

Author(s)

See Also

Examples

Date Conversion from Rata Die

Description

Usage

Arguments

Value

Author(s)

References

See Also

Examples

Converts a Date to a Decimal of its Year

Description

Usage

Arguments

Value

Author(s)

See Also

Examples

Coerce to Rata Die

Description

Usage

Arguments

Value

Author(s)

References

See Also

Examples

Year Conversion from Rata Die

Description

Usage

Arguments

Value

Author(s)

References

See Also

Examples

Coerce to a Data Frame

Description

Usage

Arguments

Value

Methods (by class)

Author(s)

See Also

Examples

Calendar

Description

Usage

Arguments

Details

Value

Note

Author(s)

See Also

Examples

Calendar Parameters

Description

Usage

Arguments

Value

Author(s)

See Also

Examples

Calendar Converter

Description

Usage

Arguments

Value

Author(s)

See Also