Quick Start: Example OOMMF Session

• STEP 1: Start up the mmLaunch window.
  • At the command prompt, when you are in the OOMMF root directory, type

    tclsh oommf.tcl
    

    (The name of the Tcl shell, rendered here as tclsh, may vary between systems.) Alternatively, you may launch oommf.tcl using whatever ``point and click'' interface is provided by your operating system.
  • This will bring up a small window labeled mmLaunch. It will come up in background mode, so you will get another prompt in your original window, even before the mmLaunch window appears.
• STEP 2: Gain access to other useful windows.
  • On mmLaunch window, check the localhost box, causing a menu of user account boxes to appear. Then check the box corresponding to the account you want to compute on. This gives a menu of options:
    • mmArchive: to auto-save vector field data (primitive)
    • mmDataTable: to display current values of variables
    • mmDisp: to display vector fields
    • mmGraph: to form x-y plots
    • mmProbEd: to grab/modify a problem
    • mmSolve2D: to control the solver
  • Click on mmDisp, mmGraph, and/or mmDataTable, depending on what form of output you want.
• STEP 3: Load a problem.
  • On mmLaunch window, click on the mmProbEd button.
  • On mmProbEd window, make menu selection File|Open... An Open File dialog window will appear.
  • On this window:
    • Double click in the Path subwindow to change directories. Several sample problems can be found in the directory oommf/app/mmpe/examples.
    • To load a problem, double click on a *.mif file (e.g., prob1.mif) from the list above the Filter: subwindow.
    • Modify the problem as desired by clicking on buttons from the main mmProbEd window (e.g., Material Parameters), and fill out the pop-up forms. A completely new problem may be defined this way.
• STEP 4: Initialize the solver.
  • On mmLaunch window, click on the mmSolve2D button to launch an instance of the program mmSolve2D.
  • Wait for the new solver instance to appear in the Threads column in the mmLaunch window.
  • Check the box next to the mmSolve2D entry in the Threads column. A window containing an mmSolve2D interface will appear.
  • On mmSolve2D window:
    • Check Problem Description under Inputs.
    • Check mmProbEd under Source Threads.
    • Click LoadProblem.
    • A status line will indicate the problem is loading.
    • When the problem is fully loaded, more buttons appear.
    • Check Scheduled Outputs.
    • For each desired output (TotalField, Magnetization, and/or DataTable), specify the frequency of update:
      • Check desired output. This will exhibit the possible output destinations in Destination Threads. Output applications such as mmDisp, mmGraph, and/or mmDataTable must be running to appear in this list.
      • Check the box next to the desired Destination Thread. This will exhibit Schedule options.
      • Choose a schedule:
        • Iteration: fill in number and check the box.
        • ControlPoint: fill in number and check the box.
        • Interactive: whenever you click corresponding Interactive output button.
• STEP 5: Start the calculation.
  • On the mmSolve2D window, start the calculation with Run or Relax.
  • If you requested mmDataTable output, check the boxes for the desired quantities on the mmDataTable window under the Data menu, so that they appear and are updated as requested in your schedule.
  • Similarly, check the box for the desired X, Y1, and Y2 variables on the mmGraph window(s) under the X, Y1 and Y2 menus.
• STEP 6: Saving results.
  • Vector field data (magnetization and effective field) may be interactively written to disk using mmDisp, or may be automatically saved via scheduled output to mmArchive. For example, to save the magnetization state at each control point, start up an instance of mmArchive and select the ControlPoint check box for mmArchive on the Magnetization schedule in the solver. This may be done before starting the calculation. (Control points are points in the simulation where the applied field is stepped. These are typically equilibrium states, but depending on the input *.mif file, may be triggered by elapsed simulation time or iteration count.)
  • DataTable data may be saved using mmGraph. Schedule output from the solver to mmGraph as desired, and use either the interactive or automated save functionality of mmGraph. You can setup the solver data scheduling before the calculation is started, but must wait for the first data point to configure mmGraph before saving any data. As a workaround, you may configure mmGraph by sending it the initial solver state interactively, and then use the Options|clear Data menu item in mmGraph to remove the initializing data point. Alternatively, you may send scheduled output from the solver to mmArchive, which will automatically save all the data it receives.
• STEP 7: Perform midcourse controls as desired.
  • On the mmSolve2D window, buttons can stop and restart the calculation:
    • Reset: Return to beginning of problem.
    • LoadProblem: Restart with a new problem.
    • Run: Apply a sequence of fields until all complete.
    • Relax: Run the ODE at the current applied field until the next control point is reached.
    • Pause: Click anytime to stop the solver. Restart with Run or Relax.
    • Field-: Apply the previous field again.
    • Field+: Apply the next field in the list.
  • Output options can be changed and new output windows opened.
• STEP 8: Exit OOMMF.
  • On the mmSolve2D window, terminate the simulation with Exit.
  • Terminate each mmArchive instance by hitting the Exit button in its user interface window.
  • Use the File|Exit menu on each remaining window to exit.

OOMMF Documentation Team
January 15, 2004