Manual Page for Command >>>> PRIOR


Syntax
>>>> PRIOR: prior_info

Parent Command
all third-level commands in block > PARAMETER

Subcommand
-

Description
This command provides the prior information of the parameter to be estimated. If command >>>> PRIOR is omitted, the value from the TOUGH2 input file is taken. Prior information is only effective if a standard deviation is provided (see command >>>> DEVIATION (p)), in which case the difference between the parameter estimate and its prior value is penalized in the objective function. The starting point for the optimization is given through commands >> GUESS and >>>> GUESS. If command >>>> LOGARITHM is present, the prior information is the logarithm of the parameter. Similarly, if command >>>> FACTOR is present, the prior information should be a multiplication factor (default is 1.0).

Example
> PARAMETER
>> ABSOLUTE permeability
>>> ROCK type : SAND1
>>>> LOGARITHM
>>>> PRIOR information : -12.0
>>>> standard DEVIATION: 1.0 order of magnitude
<<<<
>>> ROCK types: CLAY1 CLAY2 CLAY3 BOUND
>>>> FACTOR
>>>> initial GUESS : 1.0
>>>> is not WEIGHTed : 0.0 (default)
<<<<
<<<

>> GUESS, i.e., starting point for optimization
1 -13.0
<<

See Also
>> GUESS | >>>> GUESS | >>>> DEVIATION (p) | >>>> VARIATION


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Page updated: July 29, 1997