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Last data update: 2014.03.03

R: Create a new calibration curve

CreateCalCurve

R Documentation

Create a new calibration curve

Description

A function for creating a new calibration curve not already avialable in Bchron

Usage

CreateCalCurve(name,cal_ages,uncal_ages,one_sigma=rep(0,length(cal_ages)))

Arguments

`name`	The name of the new calibration curve
`cal_ages`	A vector of the calendar/calibrated ages in years before present
`uncal_ages`	A vector of values of uncalibrated ages in appropriate units (e.g. 14C years BP)
`one_sigma`	The one sigma (one standard devation) values in uncalibrated units. If left blank it assumes these are all zero

Details

Calibration curves are stored by Bchron in the standard R gzipped text format. You can find the location of the calibration curves by typing system.file('data',package='Bchron'). Any calibration curve supplied will be converted to this format and put in the appropriate directory. It can then be used as in the examples below. However note that re-installing Bchron will likely over-write previously created calibration curves so you should make sure to store the code used to create it.

Author(s)

Andrew Parnell <andrew.parnell@ucd.ie>

References

Forthcoming!

Examples

## Not run: 
# Load in the calibration curve with:
intcal09 = read.table('http://www.radiocarbon.org/IntCal09
# Run CreateCalCurve
CreateCalCurve(name='intcal09',cal_ages=intcal09[,1],uncal_ages=intcal09[,2],one_sigma=intcal09[,3])

# Calibrate the ages under two calibration curves
age_09 = BchronCalibrate(age=15500,ageSds=150,calCurves = 'intcal09',ids='My Date')
age_13 = BchronCalibrate(age=15500,ageSds=150,calCurves = 'intcal13')

# Finally plot the difference
plot(age_09)
with(age_13$date1,lines(ageGrid,densities,col='red'))
legend('topleft',legend=c('intcal09','intcal13'),col=c('black','red'),lty=1)

## End(Not run)