pdr_cost: Cost function between observed and predicted pools

In PoolDilutionR: Calculate Gross Biogeochemical Flux Rates from Isotope Pool Dilution Data

Cost function between observed and predicted pools

Description

Cost function between observed and predicted pools

Usage

pdr_cost(
  params,
  time,
  m,
  n,
  m_prec,
  ap_prec,
  P,
  k,
  pool = "CH4",
  frac_P = frac_P_default(pool),
  frac_k = frac_k_default(pool),
  log_progress = NULL
)

Arguments

params	Named list holding optimizer-assigned values for parameters
time	Vector of numeric time values; first should be zero
m	Observed total pool size, same length as time
n	Observed pool size of heavy isotope, same length as time
m_prec	Instrument precision for pool size, expressed as a standard deviation
ap_prec	Instrument precision for atom percent, expressed as a standard deviation
P	production rate, unit pool size/unit time
k	first-order rate constant for consumption, 1/unit time
pool	Name of pool; see pdr_fractionation
frac_P	Fractionation value for production; see pdr_fractionation
frac_k	Fractionation value for consumption; see pdr_fractionation
log_progress	An optional logging function

Value

Returns a cost metric summarizing the difference between the predicted and observed m (total pool size) and AP (atom percent).

Note

This implements Equations 12-14 from von Fischer and Hedin (2002).

Author(s)

K.A. Morris & B. Bond-Lamberty

Examples

m <- c(10, 8, 6, 5, 4, 3)
n <- c(1, 0.7, 0.6, 0.4, 0.3, 0.2)
pdr_cost(params = list(P = 0.5, k = 0.3), time = 0:5, m, n, m_prec = 0.001, ap_prec = 0.01)

PoolDilutionR documentation built on Feb. 16, 2023, 10:05 p.m.