algebraic_mappings

Use AMPL to define algebraic input-output mappings

Specification

  • Alias: None

  • Arguments: STRING

  • Default: no algebraic mappings

Description

Dakota can evaluate algebraic input-output mappings using AMPL [FGK03]. The mappings are expressed in 3 files: stub.nl, stub.col, and col,stub.row, where row,stub is a particular root name describing a particular problem. The file names are communicated to Dakota using the algebraic_mappings keyword. It may either specify the full stub.nl filename, or alternatively, just the nlstub basename.

Dakota then extracts the input and output identifier strings from stub.col and colstub.row and employs the AMPL solver library [Gay97] to process the directed acyclic graphc (DAG) specification in stub.nl. The variable and objective function names declared within AMPL should be a subset of the variable and response descriptors specified in the variables and responses blocks. Ordering is not important, as Dakota will reorder data as needed.

Examples

An interface employing both algebraic and simulation-based mappings. The results from the individual algebraic and simulation mappings are overlaid based on the variable and response descriptors used by the individual mappings.

interface,
 algebraic_mappings = 'ampl/fma.nl'
 fork
   analysis_driver = 'text_book'
   parameters_file = 'tb.in'
   results_file    = 'tb.out'