import numpy as np
[docs]class Params:
"""
Class to define parameters that will be estimated using PEST.
Parameters
----------
mfpackage : str
The Modflow package type to associated with this parameter.
'LPF' is one package that is working now.
partype : str
The parameter type, such as 'hk'. This must be a valid attribute
in the mfpackage.
parname : str
The parameter name, such as 'HK_1'.
startvalue : float
The starting value for the parameter.
lbound : float
The lower bound for the parameter.
ubound : float
The upper bound for the parameter.
span : dict
The span over which the parameter applies. The span depends on the
type of array that the parameter applies to. For 3d arrays, span
should have either 'idx' or 'layers' keys. span['layers'] should
be a list of layer to for which parname will be applied as a
multiplier.
idx is a tuple, which contains the indices to which this parameter
applies. For example, if the parameter applies to a part of a 3D
MODFLOW array, then idx can be a tuple of layer, row, and column
indices (e.g. (karray, iarray, jarray).
This idx variable could also be a 3D bool array. It is ultimately
used to assign parameter to the array using arr[idx] = parname.
For transient 2d arrays, span must include a 'kpers' key such that
span['kpers'] is a list of stress period to which parname will be
applied as a multiplier.
transform : Parameter transformation type.
"""
def __init__(
self,
mfpackage,
partype,
parname,
startvalue,
lbound,
ubound,
span,
transform="log",
):
self.name = parname
self.type = partype
self.mfpackage = mfpackage
self.startvalue = startvalue
self.lbound = lbound
self.ubound = ubound
self.transform = transform
self.span = span
return
[docs]def zonearray2params(
mfpackage, partype, parzones, lbound, ubound, parvals, transform, zonearray
):
"""
Helper function to create a list of flopy parameters from a zone array
and list of parameter zone numbers.
The parameter name is set equal to the parameter type and the parameter
zone value, separated by an underscore.
"""
plist = []
for i, iz in enumerate(parzones):
span = {}
span["idx"] = np.where(zonearray == iz)
parname = f"{partype}_{iz}"
startvalue = parvals[i]
p = Params(
mfpackage,
partype,
parname,
startvalue,
lbound,
ubound,
span,
transform,
)
plist.append(p)
return plist