Running Examples

To run Dakota with a particular input file, the following syntax can be used:

dakota -i dakota.in

or more simply:

dakota dakota.in

This will echo the standard output (stdout) and standard error (stderr) messages to the terminal. To redirect stdout and stderr to separate files, the -o and -e command line options may be used:

dakota -i dakota.in -o dakota.out -e dakota.err

or

dakota -o dakota.out -e dakota.err dakota.in

Alternatively, any of a variety of Unix (or Windows) command-line redirection variants can be used. The simplest of these redirects stdout to another file:

dakota dakota.in > dakota.out

Note

Command-line redirection will redirect all Dakota-generated output (or errors if specified) to the specified file, including output from underlying third-party libraries. In contrast, the command-line -output and -error (or analagous input file options) will only capture output from core Dakota and may not include some elements of console output.

To run the dakota process in the background, append an ampersand symbol (&) to the command with an embedded space, e.g.,

dakota dakota.in > dakota.out &

Refer to [AA86] for more information on Unix redirection and background commands.

The specified Dakota input file may instead be an dprepro/aprepro-style template file to be pre-processed prior to running Dakota. For example it might contain template expressions in curly braces:

# {MyLB = 2.0} {MyUB = 8.6}
variables
  uniform_uncertain 3
        upper_bounds {MyUB} {MyUB} {MyUB}
        lower_bounds {MyLB} {MyLB} {MyLB}

(See dprepro- and pyprepro- specific instructions for more information and use cases.) To pre-process the input file, specify the -preproc flag which gen- erates an intermediate temporary input file for use in Dakota. If Dakota’s pyprepro.py utility is not available on the execution PATH and/or additional pre-processing options are needed, the tool location and syntax can be specified, for example:

# Assumes pyprepro.py is on PATH:
dakota -i dakota_rosen.tmpl -preproc

# Specify path/name of pre-processor:
dakota -i dakota_rosen.tmpl \
  -preproc "/home/user/dakota/bin/pyprepro"

# Specify Python interpreter to use, for example on Windows
dakota -i dakota_rosen.tmpl -preproc "C:/python27/python.exe \
  C:/dakota/6.10/bin/pyprepro/pyprepro.py"

# Specify additional options to pyprepro, e.g., include file:
dakota -i dakota_rosen.tmpl -preproc "pyprepro.py -I default.params"

The “-pre run”, “-run”, and “-post run” options instruct Dakota to run one or more execution phases, excluding others. For example pre-run might generate variable sets, run (core run) might invoke the simulation to evaluate variables and produce responses, and post-run might accept variable/response sets and analyzes the results (for example, calculate correlations from a set of samples). Currently only two modes are supported and only for sampling, parameter study, and DACE methods:

  1. pre-run only with optional tabular output of variables:

    dakota -i dakota.in -pre_run [::myvariables.dat]

  2. post-run only with required tabular input of variables/responses:

    dakota -i dakota.in -post_run myvarsresponses.dat::