Optim_GR2MSemiDistr: Model parameter optimization with the SCE-UA algorithm.

In hllauca/GR2MSemiDistr: A package for hydrological modeling with a semi-distribute GR2M model adaptation in large-sample studies.

Model parameter optimization with the SCE-UA algorithm.

Description

Model parameter optimization with the SCE-UA algorithm.

Usage

Optim_GR2MSemiDistr(
  Data,
  Subbasins,
  RunIni,
  RunEnd,
  WarmUp = NULL,
  Parameters,
  Parameters.Min,
  Parameters.Max,
  Max.Functions = 5000,
  Optimization = "NSE",
  No.Optim = NULL
)

Arguments

Data	Dataframe with model input's data in airGR format from Create_Forcing_Inputs. (DatesR, P_1, P_2,..,P_n, E_1, E_2, ...E_n, Q). If Q is not available please provide only DatesR, P, and E.
Subbasins	Subbasins' shapefile. Must contain the following attributes: 'Area' (in km2), 'Region' (in letters), and 'COMID' (identifier number).
RunIni	Initial date of the model simulation in 'mm/yyyy' format.
RunEnd	Ending date of the model simulation in 'mm/yyyy' format.
WarmUp	Number of months for the warm-up period. NULL as default.
Parameters	Vector of initial model parameters (X1 and X2) and correction factors of P (fp) and E (fpe) in the following order: c(X1, X2, fp, fpe). In the case of existing more than one 'Region' (e.g. regions A and B) please provide model parameters in the following order: c(X1_A, X1_B, X2_A, X2_B, Fp_a, Fp_B, Fpe_A, Fpe_B).
Parameters.Min	Vector of minimum values of GR2M model parameters and correction factors in the following order: c(X1_min, X2_min, fp_min, fpe_min).
Parameters.Max	Vector of maximum values of GR2M model parameters and correction factors in the following order: c(X1_max, X2_max, fp_max, fpe_max).
Max.Functions	Maximum number of function evaluation for optimization. 5000 as default.
Optimization	Objective function for optimization (NSE, KGE, or RMSE).
No.Optim	Regions not to be optimized. NULL as default.

Value

List of optimal GR2M model parameters for each 'Region'.

Param: Best set of GR2M model parameters (sorted by 'Region').

Value: Final value of the objective function.

References

Llauca H, Lavado-Casimiro W, Montesinos C, Santini W, Rau P. PISCO_HyM_GR2M: A Model of Monthly Water Balance in Peru (1981–2020). Water. 2021; 13(8):1048. https://doi.org/10.3390/w13081048

Examples

# Optimize GR2M model parameters for a single 'Region' using the KGE metric
optim <- Optim_GR2MSemiDistr(Data=data,
                             Subbasins=roi,
                             RunIni='01/1981',
                             RunEnd='12/2002',
                             WarmUp=36,
                             Parameters=c(1000, 1, 1, 1),
                             Parameters.Min=c(1, 0.01, 0.8, 0.8),
                             Parameters.Max=c(2000, 2, 1.2, 1.2),
                             Max.Functions=1000,
                             Optimization='KGE')
 best_param <- optim$Param

hllauca/GR2MSemiDistr documentation built on March 2, 2024, 3:33 a.m.