convert a BP age scale to AD

a ggplot scale to convert a BP axis to AD

BP2AD_trans()

See also

Other plot help: AD2BP_trans(), axisLabel(), bin2d(), geoChronRPlotTheme(), getLegend(), getPlotRanges(), kde2d(), meltDistributionTable(), modeSelektor(), periodAnnotate(), quantile2d(), reverselog10_trans()