all third-level commands in block > PARAMETER
The parameter to be estimated is a factor with which the initial parameter guess is multiplied.
X=p*X0 <=> p=X/X0Here, p is the estimated parameter, X is the TOUGH2 parameter, and X0 is the initial value of the TOUGH2 parameter. This option is useful to estimate a scaling factor for variable initial and boundary conditions, or to determine the mean of a quantity while maintaining ratios (e.g., if estimating a common factor applied to all three permeability values in a model domain, the anisotropy ratio remains constant). If the factor is log-normally distributed, add command >>>> LOGARITHM or use command >>>> LOG(F). Estimating a factor is opposed to estimating the parameter value directly (command >>>> VALUE) or its logarithm (command >>>> LOGARITHM (p)).
>> ABSOLUTE permeability
>>> MATERIAL: CLAY1 SAND1
>>>> estimate multiplication FACTOR, and maintain both the
anisotropy ratio within a layer as well as the permeability
ratio between clay and sand.
>>>> INDEX : 1 2 3
>>>> initial GUESS: 1.0 (default)
>>>> RANGE : 0.01 100.0