
NairnFEAMPM Preferences
This section explain the NairnFEAMPM settings or preferences. To change the preferences, use the NairnFEAMPM->Settings... menu command, which is the Preferences... menu command prior to MacOS Ventura (10.13). The options are
Color Preferences
The color preferences set various colors used for graphics display of analysis results. Changes made to colors immediately affect open plots. The colors apply to particle plots and to mesh plots.

- Color Plot Spectrum
- For color plots, the color indicates value of the plot quantity. You can select between three rainbow spectra, a grayscale, a diverging color spectrum, four perceptually uniform spectra (Viridis, Magma, Inferno, and Plasa), and Turbo. For the rainbow spectra (only), the slider selects brightness of the colors. The perceptually uniform spectra were designed by MatPlotLib to provide an image that looks correct in both color and black and white as well as for people who are color blind. They work well when submitting figures to Journals who are unable to handle different figures for on-line color and print black and white. The Turbo spectra is decribed in a Google AI Blog; it was developed to improve on the Blue to Red rainbow, which they labeled as the "Jet" spectrum.
- Invert Spectrum
- This option inverts the color spectrum. For example, "Rainbow 2" assigns blue to the minimum and red to the maximum. By selecting "Invert Spectrum" the spectrum will assign red to the minimum and blue to the maximum.
- Discrete Contours
- If the setting is 1 or less, the coloring will be continuous (millions of colors) based on plot value at the selected location. Choosing a number greater than 1 will use that finite number of colors (determined by the entered number). A finite number of colors is sometimes clearer, such as when preparing plots for publications.
- Plot Elements
- Set color for various elements of plots. "Labels" means color of text labels.
MPM Movie Preferences
Set various options for the type of plots created when doing particle plots of MPM results. Changes made to the settings immediately affect all open particle plots.

- Material Points
- The options in this section affect drawing of the material points:
- Show Points: show material points in the plot.
- Show Point Numbers: display point numbers on top of material points (2D only).
- Square Points: material points can be plotted as circles or square boxes (if checked).
- Show Point BCs: show boundary conditions applied to material points (loads and tractions only) and show rigid particles. Loads are drawn with an arrow starting on the material point; tractions are drawn with the same arrow but starting on the particle face being loaded. Note that if the arrow points into an object, it may not be visible in 3D simulations.
- Transform Points: this setting will transform square (2D) or cube (3D) points into parallelograms (2D) or parallelepipeds (3D) according to the deformation gradient on the particle. This option gives more information in the plot and fills space better in a good analysis (in fact gaps in the plot could indicate inaccuracies in the analysis or a need for higher resolution; i.e., the deformation gradient is changing too rapidly between neighboring points). To be sure it transforms correctly, the analysis will need to archive rotational strains and if plasticity if involved, it should archive plastic strains as well. If rotational strains are not archived, the point will still transform, but will only be correct if all materials angles were initially zero; otherwise the particle rotation will be wrong. Transformation is only done when using the "Square Points" preference.
- Show Crack Planes: MPM cracks have a plane and separately track top and bottom surfaces. Select this option to show the crack plane, which applies to both particle and mesh plots. The color box sets to color for the crack plane.
- Show Crack Surfaces: Select this option to show both crack surfaces, which applies to both particle and mesh plots. The color boxes set the colors for the surfaces above and below the crack. The definition of above depends on orientation of the crack.
- Background Grid
- The options in this section select what is displayed in the background grid. The settings are self explanatory (or try them to see what happens). If "Show Mesh" is unchecked, the option to show mesh BCs (boundary conditions) is ignored. The element and node numbers only show in 2D meshes. The "Show 3D Bounds Box" only applies to 3D calculations and only takes effect when "Show Mesh" is unchecked.
- Global Minimum and Maximum
- When this option is checked, the minimum and maximum will be calculated from all frames that have be drawn for the current plot quantity. When it is not checked, the minimum and maximum will be recalculated for each frame. It is better to check it when exporting a movie.
- Width and Height
- Set the width and height for plots. It affects subsequent plots.
Mesh Plot Preferences
Set various options for the type of plots created when doing mesh plots of MPM or FEA results. Changes made to the settings immediately affect all open mesh plots.

- Show Mesh
- Show the mesh. For FEA analyses, this option shows the undeformed mesh.
- Show Displaced Mesh
- For FEA analyses, this option shows the deformed mesh. The color field sets to the color for the deformed mesh.
- Show Element Numbers
- Show element numbers on top of the elements.
- Show Mesh BCs
- Show boundary conditions applied to the mesh. This setting will be ignored if the "Show Mesh" option is unchecked.
- Clip MPM to Particles
- When checked, mesh plots of MPM results will be clipped to an outline of the particles (created using current MPM Movie Preferences). This option allows plots of grid results to reflect the boundaries of objects. It is slower, however, because it has to draw twice - once to outline the particles and once to draw mesh results.
- Subelement Density
- When coloring mesh plots, each element is divided into subelements. This setting selects the resolution of the subelements. Higher numbers give smoother colors but take longer.
- Show Contours in:
- For FEA calculations, the colors can be in the initial, undeformed mesh or in the displaced mesh. When contours are in the displaced mesh, element numbers, nodes, and node numbers will be in the displaced mesh too.
- Show Nodes
- Show small circles on all nodes.
- Show Node Numbers
- Show node numbers up and to the right of each node.
Code Preferences
The code preferences determine the paths to the FEA and MPM code engines (NairnFEA and NairnMPM), whether or not the input XML
commands are validated prior to running the code, and the paths to the FEA or MPM DTD
files (DTD
or data template definition files are used to validate the XML
commands).
When NairnFEAMPM is first installed on a Mac, these settings will be "$(bundle)," which means to use the code engines and DTD files bundled inside the NairnFEAMPM app. This option is no longer used. Before you can run calculations, you will have to install all required binaries and then enter paths to those binaries in these preferences.

- Paths to Code Engines
- Enter the full path to the NairnFEA and NairnMPM code engines being compiled when installing the binaries. You can use "~" to start the path in your home directory, if desired. Otherwise enter the full path to the code engines. Click the magnifying glass icons to select the binary using a standard open-file dialog box.
- Validate input XML file using current DTD file
- Checking this option will use advanced
XML
parsing methods to validate the inputXML
commands before starting the calculations. It is usually better to select this option. It can be unchecked if theDTD
files used for validation are missing or out of date. - FEA and MPM
DTD
Files DTD
files are used to validateXML
files for proper formatting. Enter paths to the FEA and MPMDTD
files in these two fields. From the checked-out code, the relevant DTD files will be found in theNairnMPM/input
andNairnFEA/input
folders of the project. You can use "~" to start the path in your home directory, if desired. Otherwise enter the full path to theDTD
files. Click the magnifying glass icons to select the DID files using a standard open-file dialog box.
Other Preferences
This last tab has some miscellaneous preferences as follows:

- Export Graphics Format
- This options is no longer available. You now pick graphics format by using that format's extension when choosing where to save the file. The supported options are pdf, tiff, jpg, png, and bmp.
- Save commands before running an analysis
- When checked, NairnFEAMPM will automatically save edits to the input commands before starting an analysis. Note that this autosave does not work for commands in a new "Untitled" command file that has not yet been saved.
- Check for update on start up
- When checked, NairnFEAMPM will check the web to see if a new version is available for downloading. This check causes no delay in start up because it is run in a separate thread. It is best to leave it checked.