Simple Example

Dakota GUI

The following is a minimial, quick start guide. For more information on features available in the GUI (such as graphical plotting), consult the Dakota GUI manual.

First Steps

  1. Make sure the Dakota GUI launches.
    1. At a minimum, you will need Java 1.8 JDK (not a JRE) installed as a prerequisite.  The latest JDK is available from Oracle.
  2. Using the first dialog that appears, choose the folder you'd like to set as your Dakota GUI workspace.  If you're not sure, use the proposed default of "dakota_gui_workspace" in your system's home directory.
  3. You should now see the Welcome screen.  Select "Search the Dakota examples repository."
    1. If a dialog appears telling you that the Dakota path has not been set, the dialog should also present you with a recommended choice for which command-line Dakota to connect to.  The recommended choice should be the instance of Dakota located in the "bin" directory relative to the location of the Dakota GUI.
  4. In the "Dakota Examples Search" dialog, type "rosen" in the search field and click "Search."  Select "rosen_multidim.in" from the list of search results, then select "Download."  Once the rosen_multidim.in example is imported, you should see a new Dakota GUI project named "rosen_multidim" created for you in the Dakota Project Navigator pane.  In addition, you should see the rosen_multidim.in file loaded in the text editor in the middle of the screen.
  5. From the Run menu at the top of the screen, select Run As > Dakota.  You should see Dakota running in the Console view in the bottom-right corner of the screen.  When Dakota is finished running, some new files will be added to your project.

What should happen

Dakota outputs a large amount of information to help users track progress.

By default, the output and error streams of Dakota will be printed out to the Console view (the output stream will be displayed using black text; the error stream will be displayed using red text).

Two files should have been created.

  1. Tabular Data:  The file rosen_multidim.dat is created due to the specification of the tabular graphics data file. This summarizes the variables and responses for each function evaluation.
  2. Restart File:  The file dakota.rst is a restart file. If a Dakota analysis is interrupted, it can be often be restarted without losing all progress.

In addition, these files will be backed up into a time-stamped directory in your GUI project (see the run_results/ parent directory).

What now?

  • Assuming Dakota ran successfully, skim the console output and tabular data file. These are described further in the Dakota User's Manual, Section 2.1.3.
  • This example used a parameter study method, and the Rosenbrock test problem. More details about the example are in Dakota User's Manual, Section 2.3.2 and the test problem is described in Sections 2.3.1 and 21.2.
  • Try running other Rosenbrock examples, importable from Dakota's shipped examples using the search dialog.
  • Explore the many methods available in Dakota in the Dakota User's Manual, Chapters 3 - 8.
  • Learn the syntax needed to use these methods. For running Dakota see the Section 2.4, and for input file information see Section 2.2.
  • Learn how to use your own analysis code with Dakota in Chapter 17.
  • Learn how to graphically plot data collected in the tabular data file.  See Chapter 7 of the Dakota GUI Manual.

Dakota on the Command Line

In addition to the short guide below, a more detailed tutorial is available in Chapter 2 of the Dakota User's Manual.

First Steps

  1. Make sure Dakota runs.
    You should see Dakota version information when you type:
    dakota -v
  2. Create a working directory for your Dakota files.
  3. Copy rosen_multidim.in from the $DAKOTA_INSTALL/share/dakota/examples/users directory to the working directory, where $DAKOTA_INSTALL is the Dakota installation directory.
  4. From the working directory, run:
    dakota -i rosen_multidim.in -o rosen_multidim.out rosen_multidim.stdout

What should happen

Dakota outputs a large amount of information to help users track progress. Four files should have been created:

  1. The screen output has been redirected to the file rosen_multidim.stdout. The contents are messages from Dakota and notes about the progress of the iterator (i.e. method/algorithm).
  2. The output file rosen_multidim.out contains information about the function evaluations.
  3. The file rosen_multidim.dat is created due to the specification of tabular graphics data and tabular graphics file. This summarizes the variables and responses for each function evaluation.
  4. The file dakota.rst is a restart file. If a Dakota analysis is interrupted, it can be often be restarted without losing all progress.

In addition to the files, some plots are created due to the specification of graphics. These can be helpful when processing the data or diagnosing unexpected results. Dakota has some data processing capabilities built in. The output file will contain the relevant results. In this case, the output file has details about each of the 81 function evaluations. For more advanced or customized data processing or visualization, the tabular data file can be imported into another analysis tool.

What now?

  • Assuming Dakota ran successfully, skim the three text files (restart files are in a binary format). These are described further in the Dakota User's Manual, Section 2.1.3.
  • This example used a parameter study method, and the Rosenbrock test problem. More details about the example are in Dakota User's Manual, Section 2.3.2 and the test problem is described in Sections 2.3.1 and 21.2.
  • Explore the many methods available in Dakota in the Dakota User's Manual, Chapters 3 - 8.
  • Try running the other examples in the same directory. These are mentioned throughout the Dakota User's Manual and listed in Chapter 2, Table 2.1 for convenience.
  • Learn the syntax needed to use these methods. For running Dakota see the Section 2.4, and for input file information see Section 2.2.
  • Learn how to use your own analysis code with Dakota in Chapter 17.