Calibrate organic d15 values with the given standards
calibrate_d18( data, d18, amount = amount, volume = volume, cell_volume, standards = c(`USGS-34` = -27.93, `IAEA-NO3` = 25.61), quiet = FALSE )
| data | (can be a grouped_by data set) |
|---|---|
| d18 | the d18 column |
| amount | the amount column |
| volume | the volume column |
| cell_volume | the volume of cells in the vial (has to be same units as volume!) |
| standards | a set of isotope standards Note: they are matched to the data by "category" (not by name) |
| d15 | the d15 column (can be a column already calibrated for denitrifier method) |
| infer_NO3_blank | whether to infer the NO3 blank from this correction in addition to the organic blank (if using a single step correction) |
| ref_gas_d15 | the reference gas isotopic composition (only used if infer_NO3_blank = TRUE, to constrain culture blank d15) |
introduces the column d15.ocal and parameters p.15o_stds, p.d15o_m_true, p.d15o_m_vol, p.d15o_m_true:vol and p.d15o_b as well as information on the organic blank p.No_blk_conc and p.No_blk_d15 and nitrate blank (only if type is 1-step!) p.N_blk_amt and p.N_blk_d15
introduces the column d18.cal and parameters p.d18_m_true, p.d18_m_conc, p.d18_m_true:conc and p.d18_b
implement single point correction Calibrate d18 data with the given standards.
Uses a multivariate linear regression that takes the effective concentration in the sample vials into consideration (as well as covariance between standards and effective concentration).
FIXME: this should have a term for evaluating whether any extrapolation happens unepxectedly that then causes trouble!!