Version 3.1 (2003/04/04)

New iterative methods

  • Optimization:

    • NPSOL v5.0 update.

    • OPT++ method consolidation (from 15 down to 6) and additional constraint coverage (added BCFDNewton and GNewton NIPS).

    • Initial rSQP++/MOOCHO interface (large-scale optimization).

    • Initial COLINY interface for access to APPS and DIRECT optimizers.

  • Uncertainty quantification:

    • New f90 LHS library (not yet publicly available).

      • restricted pairing: enforces the desired correlation in the sample set, whether inducing a user-specified correlation or minimizing correlation for the default uncorrelated case.

      • bounded normal and bounded lognormal distributions

      • bin-based and point-based histogram distributions

      • additional output: sample histograms and achieved correlation in f90 output, coefficient of variation and confidence interval statistics in DAKOTA output.

      • consolidation of old/new sampling for LHS/PCE

    • MV/AMV/AMV+/FORM reorganization.

  • Parameter estimation:

    • New NLSSOL SQP-based generally-constrained nonlinear least squares.

    • New least squares iterator branch to support NLSSOL and OPT++ GNewton.

  • Sensitivity/statistical analysis:

    • Distribution of DDACE under LGPL.

    • Consolidation of function evaluation management routines among design of experiments, UQ sampling, and parameter studies.

New strategies

  • Surrogate-based optimization

    • Enhancements to penalty function consistency.

    • Enhancements to trust region management and convergence controls.

    • New 1st-order additive correction (thanks to Natalia Alexandrov and Michael Lewis for formulation). Improves convergence in SBO test cases employing hierarchical surrogates.

  • Optimization under uncertainty (OUU)

    • New trust-region surrogate-based OUU (paper).

    • Enhanced data flow in Layered/Nested models.

  • Concurrent (Pareto set, Multi-start)

    • New random starts capability (in place of or in combination with user-specified starts).

    • New results/timing summaries.

    • Parallel scheduling enhancements.

New DAKOTA facilities

  • New library mode:

    • Library creation (libdakota.a et al.) and consolidation in Dakota/lib.

    • New API for cases when command line arguments are not directly accessible.

    • Access to final strategy results.

    • Library mode documentation.

  • New surrogates:

    • Linear and cubic polynomials to supplement existing quadratic polynomial.

  • Enhanced random seed control for multiple sampling sets in DDACE and LHS

    • 4 seed selections: combinations of fixed vs. sequenced and user-specified vs. system-generated.

    • Sequenced seeds result in variable sampling patterns which enhance reliability and accelerate convergence in SBO, OUU, and SBOUU.

  • New error checking in approximation classes, uncertain variables, PCE, submodel compatibility, and method constraint support.

  • Efficiency enhancements:

    • Dropped pre-ANSI C++ mode which allowed for STL streamlining and optimization.

    • Additional output control: debug/verbose/normal/quiet/silent settings, -i/-o/-e command line options.

    • Evaluation cache and restart deactivation option.

    • New MPI intra-communicators to streamline message broadcasts for large parallel runs.

    • Streamlined communicator repartitioning in strategies.

  • New utilities:

    • Restart repair by evaluation id.

    • 3D graphics fonts (PLplot) distributed with executables.

  • SQA: - Automated DAKOTA testing: nightly build verifications, new regression test facilities employing test matrices, unit testing under development. - Nightly library testing for SGOPT, PICO, and UTILIB (OPT++, DDACE to follow). - Requirements/issue tracking (Bugzilla, restricted access), design tracking, release management (automated posting of nightly builds available shortly).

Contributions from the user community

  • Distributed testing/issue identification:

    • SGOPT: problem size limitations removed (identified by Michel Beaulieu), real-valued GA bound constraint bug resolved (identified by Hongman Kim), multi_step keyword mismatch resolved (identified by Don Flaggs).

    • OPT++: bound constraints fixed in PDS (identified by Don Flaggs), final solution returned properly (identified by Michel Beaulieu).

    • DOT/CONMIN: registration of automatic method switches for consistency in output headers (identified by Don Flaggs).

    • SBO fraction of cauchy decrease bug resolved (identified by Myles Baker).

    • LINUX graphics configuration generalized (identified by Constantine Orogo).

    • IBM POE: replaced short hand checks for MPI_REQUEST_NULL (identified by Scott Brandon).

    • DEC asynchronous evaluations: activated usleep() function in asynch schedulers as OSF 5.1 is now supporting it (identified by Scott Brandon).

  • Enhancement suggestions:

    • Surrogate builds from files (requested by Srinivas Kodiyalam)

    • Output of surrogate functional forms (requested by Srinivas Kodiyalam).

    • Seed output from SGOPT to allow run recreation (requested by Don Flaggs).

    • Response function descriptors (requested by Hongman Kim).

  • Contributed code:

    • Cygwin evaluation and initial port (contributed by Hongman Kim).

    • Mac OSX evaluation (contributed by Carl Hagelberg).

    • Linear polynomial surrogate model (contributed by Myles Baker).

    • Direct interface to Phoenix Integration’s ModelCenter and merged variable descriptors (contributed by Hongman Kim).