Describe dates in CQL

The CQL commands R_Date, F14C_Date, C_Date and Date are used to describe individual dated events in a model. R_Date and F14C_Date represent radiocarbon dates expressed in radiocarbon years (the conventional radiocarbon age, CRA) or fraction modern (F14C) respectively. C_Date represents a calendar date. Date directly specifies a date in OxCal's internal format.

Usage

cql_r_date(name, date, error)

cql_c_date(name, date, error)

cql_r_f14c(name, date, error)

cql_date(name, date)

Arguments

name

Character. Date label(s), usually a lab code.

date

Numeric. Date or dates expressed in radiocarbon years (cql_r_date()), F14C (cql_f14c_date()), calendar years (cql_c_date()), or OxCal's internal format (cql_date()) See details.

error

Integer. Uncertainty associated with the date(s).

Value

A cql object, or a list of cql objects if the arguments are vectors.

Details

The era expected for calendar dates (BP or BC/AD) depends on a global option in OxCal, which defaults to BC/AD. BC dates are specified as negative values.

F14C measurements are recommended for modern, "post-bomb" radiocarbon dates (Reimer et al. 2004) .

OxCal's internal date format, used with Date(), is a decimal Gregorian year, for details see: https://c14.arch.ox.ac.uk/oxcalhelp/hlp_analysis_calend.html

References

https://c14.arch.ox.ac.uk/oxcalhelp/hlp_analysis_inform.html#date

https://c14.arch.ox.ac.uk/oxcalhelp/hlp_commands.html

Reimer PJ, Brown TA, Reimer RW (2004). “Discussion: Reporting and Calibration of Post-Bomb 14C Data.” Radiocarbon, 46(3), 1299–1304. ISSN 0033-8222, 1945-5755. doi:10.1017/S0033822200033154 .

See also

Other CQL functions: cql(), cql_boundary(), cql_n(), cql_options(), cql_other, cql_phase(), cql_sequence(), write_oxcal()

Examples

# Radiocarbon date
cql_r_date("ABC-001", 10100, 50)
#>  // CQL2 generated by stratigraphr v0.5.0
#>  R_Date("ABC-001", 10100, 50);

# Calendar date
cql_c_date("ABC-002", -5000, 50)
#>  // CQL2 generated by stratigraphr v0.5.0
#>  C_date("ABC-002", -5000, 50);

# F14C date
cql_r_f14c("ABC-003", 5000, 10)
#>  // CQL2 generated by stratigraphr v0.5.0
#>  F14C_date("ABC-003", 5000, 10);

# Date in OxCal internal format
cql_date("ABC-004", 2020.5)
#>  // CQL2 generated by stratigraphr v0.5.0
#>  Date("ABC-004", 2020.5);

# Vectorized: multiple dates at once
cql_r_date(c("ABC-001", "ABC-002"), c(10100, 10200), c(50, 50))
#>  // CQL2 generated by stratigraphr v0.5.0
#>  R_Date("ABC-001", 10100, 50);
#>  // CQL2 generated by stratigraphr v0.5.0
#>  R_Date("ABC-002", 10200, 50);