
Particle Plots and Movies
The Particle Plots option plots results of 2D or 3D MPM calculations by plotting the positions of all particles. The particles can be colored for its properties such as stress, strain, etc.. A slider can select the time to plot; other controls can run through time steps to run a movie of the results or control view of 3D results. Sample 2D and 3D particle plot windows are shown below. More details and particle plot options are given below the window.


For 2D plots the x axis will be horizontal, and the y axis will be vertical. For 3D plots, the initial plot will have a right-handed system with the z axis in the vertical direction and you will be looking towards the origin midway between the x and y axes. The positive x axis will move forward to the left and the positive y axis will move forward to the right. The initial coordinates are thus:

You can check the "Show 3D Bounds Box" option to show a box around the 3D coordinates and label the three axes.
Options in Particle Plots and Mesh Plots
Plot Details
To select the calculation result to plot and various other options for both particle plots and mesh plots, click the blue icon arrow to show or hide an window panel with plotting options:
- Quantity
- Select the calculation result to plot from the pop-up menu. See table of calculation results for details. Any disabled items are not available for plotting either because they do not apply to the calculation results or they were not archived in an MPM analysis or output in an FEA analysis. Select the Expression... item to plot an expression of analysis results.
- Tensor
- If the selected plot quantity is a tensor, select which component of the tensor to plot from this pop up menu.
- Vector
- If the selected plot quantity is a vector, select which component of the vector to plot from this pop up menu.
- Angle
- For tensor or vector quantities, you can rotate the coordinate system about the z axis to plot that quantities in the x-y plane in a direction not aligned with the analysis axes. Enter a clockwise direction in degrees. For example, entering 90˚ when plotting σyy will rotate the
y
axis to thex
axis and plot σxx instead. - Diameter
- Select diameter of particles in the plot as percent of the cell size. This option is for MPM particle plots only.
- Max F
- When the plot transforms particles, this option will limit the maximum deformation allowed in that transformation. For example, when modling liquids, some particles evolve into thin needles. Limiting maximum deformation allowed in plots sometimes gives better looking plots.
- Zoom
- Choose a zoom level for the plot. You can also click on the plot to zoom in at that location.
- Key
- Initially the key will show the maximum and minimum values for the plotted quantity and a color scale for values between those limits. Click the Fixed check box to customize the limits to any other range. Click the Fixed check box again to revert to the default limits (to change limits instead of reverting to default limits, hold option key when click the check box).
Movie Controls
For MPM particle and MPM mesh plots, there will be movie controls on left edge of the tool bar. You can drag the slider to select any time result from the calculations. Click the play button to scroll through the frames (as fast as possible). That button will change to a pause button while the movie is running, which can be clicked to stop the movie. Click the rewind button to go to the first frame. If you have both a particle plot and a mesh plot open for the same calculation, the movie controls will run both plot views. For faster movies, close one of the plotting windows.
To save a movie, click the .mov button and select a folder and a root file name such as "Frames.ext". NairnFEAMPM will not actually save a movie, but it will save one file for each frame starting from the current time until the maximum time. The files will be saved as "Frames0001.ext", "Frames0002.ext", etc., where frame number is inserted between root file name and the extension and the extension determines the type of files saved. The current options for 2D movies are pdf, tiff, jpg, png, and bmp. 3D movies have the same options except cannot use pdf. Once all frame files are saved, you can use other software (such as ImageJ) to link the frames into a movie (saving as avi is recommended).
2D Only: If you want to clip the results for the movie, click and drag a rectangle over the desired region first. Once dragged you can click in the rectangle to move it or outside the rectangle to remove it.
3D Only: Recent MacOS's have changed the options for accessing bit map images created in 3D OpenGL graphics (and Apple has "deprecated" use of OpenGL in Mac Apps too). The current method used by NairnFEAMPM is to do screen grabs for a rectangle with the plot. As a consequence, after starting a move, do not move the NairnFEAMPM window or cause any other applications open on top of that window.
3D View Controls
You rotate the three dials to rotate the object around the x, y, or z axis, respectively, in the coordinates of the object. You can also type an angle (and then return or tab) into the text field to get a new rotation angle. Finally, each use of up or down arrow keys in the field will increment that angle ±5 degrees and redraw.
You can drag the upper slider to zoom in or out on the object. You can also type a distance (and then return) into the text field to select a zoom value (it is a viewing distance and thus larger numbers zoom out and smaller numbers zoom in).
You can drag the lower slider to set a clipping plane and therefore view the inside of the object. You can also type a clipping plane distance (and then return) into the text field.
Exporting Graphics
You can export the current graphics using the File→Export→Graphics File (types)... menu command. You choose the type by using the extension of the desired type for the saved file name.
2D Only: If you want to clip the export, click and drag a rectangle over the desired region first. Once dragged you can click in the rectangle to move it or outside the rectangle to delete it.
Mouse Options
2D Plots
You can move the mouse over the plot. As you move, the fields on the right of the tool bar will display the current position (x
and y
) and the current plot quantity value (in z
). The pt
field will display the material point number when the mouse if over a material point. The nd
and el
fields will display the closest node and element number when the mouse is over the mesh.
If you control click on the plot, a pop-up menu will appear and and let you plot create a
2D mesh plot in either the vertical or horizontal direction through the clicked point.
If you are over a material point in a particle plot (as indicated by a point number in the pt
field),
you will also have an option to create a time plot for that particle.
3D Plots
You can click and drag to grab the model and move it in space.
You can option-click and drag in the vertical direction to zoom in or out on the plot. This drag is same as using the zoom slider.
You can command-click and drag in the horizontal or vertical direction to rotate the about about the object's x or y axis, respectively. These rotations are the same as using the x-axis or y-axis rotation tool.
You can option-command-click and drag in the horizontal direction to rotate the about about the object's z axis. This rotation is the same as using the z-axis rotation tool.
You can shift-click and drag in the horizontal or vertical direction to slide the position observed at the center of the view in the x or y direction, respectively. The sliding is done in the model coordinates and may not correspond to the dragging direction.
You can option-shift-click and drag in the vertical direction to slide the position observed at the center of the view in the z direction. The sliding is done in the model coordinates and may not correspond to the dragging direction.
Note: Large calculations might be too slow to redraw as you drag and instead and will only redraw when you release from the drag.
Zooming Options
2D Plots
You can use the pop-up menu window pane on the right (click blue arrow icon to reveal it if not showing) to zoom the window to various sizes. To zoom in on a particular point, command click on the point. To zoom out at a particular point, option-command-click on the point.
3D Plots
You can option-click and drag in the vertical direction to zoom in or out on the plot. Alternatively, you can use the zoom slider.
Scaling Plot Coordinates
If desired, you can change the units used for position and time by using the Analyze→Scale Plots... menu command. This command is only active when the results window is in front. If you change the units, the current plots will close and you can open new plots using the new units.
If the length units make the range in coordinates for the plot too small (total range <0.01), an idiosyncrasy of the Macintosh graphics environment will cause the graphics to scroll incorrectly or fail to update properly. The solution is to select smaller units (such as nm or ≤ m) instead of larger units. When results initially open, they will use the default units of mm and msec, but if the total ranges with those units are too small, the length units may automatically be changed to nm of µm instead.
Customize with Settings (or Preferences)
You can use the NairnFEAMPM settings/preferences to customize many features of the plots such as color scale, various plot feature colors, what details of the mesh and results are plotted, and the size of the plots. Changes made in the settings/preferences will affect all current and future plots.