bd_assess_calib_curve_equif: Assess the equifinality or time spans in the input...
In MichaelHoltonPrice/BayDem: Bayesian Demography

Description Usage Arguments Details Value

View source: R/bd_assess_calib_curve_equif.R

Assess the equifinality or time spans in the input radiocarbon calibration curve

1	bd_assess_calib_curve_equif(calibDf, equiList = NA)

`calibDf`	The calibration data frame, with columns yearBP, uncalYearBP, and uncalYearBPError
`equiList`	(Optional) The result of a call to bd_calc_calib_curve_equif_dates

The input calibration data frame has three columns: yearBP, uncalYearBP, and uncalYearBPError. A time span is equifinal if, for each date in the span, there is at least one other date in the radiocarbon calibration curve with the same fraction modern value. Conversely, a time span is not equifinal if this is not true (all dates in the time span correspond to a unique fraction modern value). Thus, the calibration curve is divided into alternating equifinal and non-equifinal spans. This function identifies these regions for the input calibration data frame, calibDf.

Although calibDf uses year BP, all calculations and returned data use AD.

A list is returned with two named variables: canInvert and invSpanList (inv = invert, which is conceptually identical to non-equifinal).

canInvert is a boolean that indicates whether each entry (row) in the calibration data frame, calibDf, is inside or outside an invertible region.

invSpanList is a list summarizing information about all the invertible (non- equifinal) time spans. It contains the following named variables:

ind – Indices (rows) of calibDf following within the invertible time span y_left – Calendar date (AD) of the left (earlier) boundary of the invertible time span phi_left – Fraction modern value of the left (earlier) boundary of the invertible time span y_right – Calendar date (AD) of the right (later) boundary of the invertible time span phi_right – Fraction modern value of the right (later) boundary of the invertible time span ii_prev – The index (row) of the calibDf earlier than the invertible region with closest fraction modern value ii_next – The index (row) of the calibDf later than the invertible

A list of with named variables canInvert and invSpanlist (see details)

MichaelHoltonPrice/BayDem documentation built on Sept. 12, 2019, 9:26 p.m.