Defining the Coloring and Style
Depending on the plot type and space dimension, the following options are available and defined under Coloring and Style. The items are listed in alphabetical order.
Arrow Base
Select Tail (the default) to position the arrow’s tail at the arrow position, Head to position the arrow’s head at the arrow position, or Center to position the center of the arrow at the arrow position.
Arrow Length
Select an Arrow length:
Proportional (the default), so that the length of the arrows is proportional to the magnitude of the quantity they represent.
Normalized, so that all arrows have the same length.
Logarithmic, so that the length of the arrows is proportional to the natural logarithm of the magnitude of the quantity they represent. This makes arrows representing small values relatively larger. The value in the Range quotient field (default: 100) determines the ratio between the smallest and largest values in the range of values for the logarithmic arrow length.
Number of Arrows
When Uniform or Uniform anisotropic is selected as the Placement, also specify the Number of arrows (default: 200).
Arrow Scale Factor
Select the Scale factor check box to enter a scalar number to scale the arrows or use the slider to select.
Arrow Type
Select an Arrow type: Arrow, Arrowhead, or Cone. Also, for Arrow Volume, Arrow Surface, Arrow Line, Arrow Point, Point Trajectories, and Ray Trajectories plots, select Double arrow for a double arrow with two arrowheads, which can represent a moment or torque, for example. Arrowheads are not available for Principal Stress and Coordinate System plots. When selecting the Ellipse point style type in Point Trajectories and Ray Trajectories plots, you can select None from the Arrow type list to not display any arrows.
Color
Surface and Contour Plots
For surface and contour plots, for example, from the Coloring list select to use a Color table (see Coloring) or select Uniform to use a single color from the Color list. You can also select Custom to define a custom color from the colored list below (on Windows) or by clicking the Color button (on Linux and macOS) and then selecting a color from the color palette.
Arrow Plots
For arrows, and unless a Color Expression subnode determines the arrow colors, select an arrow Color or select Custom to define a custom color from the colored list below (on Windows) or by clicking the Color button (on Linux and macOS) and then selecting a color from the color palette.
Graph Plots — Colors and Color Cycles
For lines in graph plots, select a Color: Custom, Cycle, Cycle (reset), From theme, Black, Blue, Cyan, Gray, Green, Magenta, Red, White, or Yellow.
If you select Custom, define a custom color from the colored list below (on Windows) or by clicking the Color button (on Linux and macOS) and then selecting a color from the color palette. Choose or enter a line Width as a positive integer, or use the slider to select. By default, the line width is set a the Default from preferences, with the width from the preference setting shown in parentheses (default: 1). You specify the default line width as a positive integer on the Graph Plots page under Results>Plots in the Preferences window.
If you select Cycle, it cycles through all the colors; if you have more than one line plot in a plot group and want to cycle through the same set of colors, select Cycle (reset). Also, choose Default (7 colors) or Long (19 colors) from the Color cycle list. Choosing Long can be useful if you plot many curves in a graph plot. The colors are defined in a text file. For information about the file format, see Color Tables and Color Themes in the COMSOL Multiphysics Programming Reference Manual.
If you select From theme, the line and maker color is taken from the selected color theme.
For Error Bars and Graph Marker subnodes, you can choose From theme to use the color from the color theme or Custom to define a custom color, or choose any of the predefined colors.
The Color Palette
In the color palette that opens, you can choose from a number of basic colors, or click Define custom colors to open a section where you can specify a specific color using sliders to define the R (red), G (green), and B (blue) components. You can also click one of the RGB values to enter a specific value (0–255). Additionally, it is possible to change the hue using the vertical color slider. To change the intensity and saturation, move the cursor in the larger area to the left of the color slider: move it up or down to add tint (more white) or shade (more black), respectively; move it to the left or right to add less or more saturation, respectively. Click Add to custom colors to add the new color to the set of available custom colors. The color palette in the cross-platform version of the COMSOL Desktop looks slightly different but provides similar functionality.
Color Legend
The Color legend check box is selected by default. Click to clear the check box if required. The legend position is determined by the settings in the Color Legend section in the Settings window for the parent Plot Group node.
You can adjust the default precision settings if required. Open The Preferences Dialog Box and click Graphics and Plot Windows. Under Display format (number of digits), in the Color legend field, enter an integer between 1 and 15 for the number of digits for the values displayed on the color legend. The default setting is 5 digits.
Color Table Transformation
Choose one of the following options from the Color table transformation list:
None (the default)
Reverse, to reverse the color table
Nonlinear
Nonlinear symmetric
With the Nonlinear and Nonlinear symmetric settings you can select the Reverse color table check box if desired. You can also transform the color table to make it nonlinear. There is a parameter that controls how much the color table is transformed. Use the Color calibration parameter field or the associated slider to define a parameter value between 1.5 and 1.5. The Nonlinear symmetric setting is mainly useful when Scale is Linear symmetric and a symmetric color table such as Dipole or Wave is used. The reversal of the color table is applied before the nonlinear transformation, if used.
Color Table Type
For Surface plots, choose Continuous (the default) or Discrete from the Color table type list. If you chose Discrete, specify the number of discrete color bands in the Number of bands field (default: 10).
Coloring
Select a Coloring: Color table (default), Uniform, or Gradient.
If Color table is selected, and if the default color table (Rainbow in most plots) is not suitable for the plot, try other options. See Selecting Color Tables for details.
If Uniform is selected, select a Color or Custom to choose a different color. For Line plots in 2D and 3D, you can also choose From theme to use the line color from the chosen color theme.
If Gradient is selected, define the coloring as a gradient between two colors, which you specify from the Top color and Bottom color lists.
Reverse Color Table
Select the Reverse color table check box to reverse the order of the colors in the color table (if Coloring is set to Color table).
Reverse Color Gradient
Select the Reverse color gradient check box to reverse the order of the colors in the color gradient (if Coloring is set to Gradient).
Ellipse Axis Expressions
Define the semi-major and semi-minor axes of the ellipse using vector expressions. For the Semi-major axis expression and Semi-minor axis expression, click the Replace Expression button () to select a predefined expression to replace the current expression, or press Ctrl+Space to insert a predefined expression (dimensionless). The expressions available are based on the physics interfaces used in the model. If the Geometrical Optics interface is used to compute ray intensity, the default expressions (typically gop.pax, gop.pay, and gop.paz for the semi-major axis and gop.pbx, gop.pby, and gop.pbz for the semi-minor axis) represent the shape and orientation of the polarization ellipse.
Ellipse Entry Method
Define the entry method for an ellipse as the point type from the Ellipse entry method: Choose Number of ellipses to enter a Maximum number of ellipses, or choose Collection of times to enter a number times in the Times field.
Ellipse Scale Factor
Select the Ellipse scale factor check box to enter a scalar or use the slider to select.
Function Type
Available for Point Graph and Global 1D plots, you can choose Continuous (the default) or Discrete from the Function type list. Choose Discrete to plot global and point graphs as discrete values.
Fixed Size
Select the Fixed size check box to make the sphere radii have constant radius when zooming a plot using one of the following particle-style plot types that plot spheres in 2D and 3D: Particle Trajectories, Ray Trajectories, and Point Trajectories; Particle Tracing and Particle Tracing with Mass; Poincaré Map; and Phase Portrait.
Function
In a Table Surface plot, choose Continuous (the default) to consider the (x, y, data) triplets as samples of a function data = f( x, y), where f( x, y) is continuous, or choose Discrete to treat the samples as discrete and draw them as large pixels.
Grid
Select a Grid: None (the default), Fine, Normal, or Coarse. If Fine, Normal, or Coarse is selected, also choose a Color for the grid.
For the Matrix Histogram plot (available with the Fatigue Module), you can select the Grid check box to add a grid to the matrix histogram. Choose a color (default: gray) for the grid from the Color list.
Interpolation and Number of Interpolated Times
Particle trajectories can appear jagged because the output times for the simulation are too few to result in a smooth plot. You can improve the particle trajectories by using a uniform interpolation of the data for the particle trajectories. From the Interpolation list, select None for no interpolation (the default), or select Uniform to use a uniform interpolation of the data using additional interpolated times defined in the Number of interpolated times field. The default is 100 interpolated times.
Legend Type
For contour, isosurface, and directivity plots, the Legend type list is available. You can choose Automatic (the default for contour and directivity plots; not available for isosurfaces), Filled for a filled (joined) legend, or Line (the default for isosurface plots), for a legend with separated lines for the levels. The Automatic setting provides a filled legend for filled contours and a line legend for line and tube contours.
Line Markers or Marker Type
Select a Marker type: None, Cycle, Cycle (reset), Asterisk, Circle, Diamond, Plus sign, Point, Square, Star, or Triangle.
If a marker is selected (excluding None), then from the Positioning list, select Interpolated (the default) or In data points or (for Line Graph, Radiation Pattern, and Through Thickness plots) In evaluation points. For Interpolated, enter the Number of markers to display (the default is 8; the maximum is 10,000 markers) or use the slider to select. If In data points is selected, the markers appear in the data points for the plot (which for a plot of a 1D solution are the mesh nodes).
If a graph plot contains isolated points, they appear as markers if the Position is set to In data points or In evaluation points; otherwise, isolated points are not visible when using markers.
Line Style
The line styles available depend on the type of plot and the space dimension and include these options:
From the Line list (for line graphs and point graphs, for example): Cycle, Cycle (reset), Solid, Dotted, Dashed, or Dash-dot. If you select Cycle, it cycles through all the colors; if you have more than one line plot in a plot group and want to cycle through the same set of colors, select Cycle (reset).
From the Line type or Type list (for line, streamline, and particle trajectory plots, for example): Line, Tube, or None (None is not available for Line plots). For 3D Streamline, Particle Trajectories, Point Trajectories, and Ray Trajectories plots, Ribbon is also available. Ribbons are an alternative to tubes for visualization of, for example, the vorticity of a flow field.
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If Tube is selected, enter a Tube radius expression (the radius of the tube); click the Replace Expression button () to select a predefined expression to replace the current expression, or press Ctrl+Space to insert a predefined expression (SI unit: m). The default is 1 m.
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If Ribbon is selected for streamlines, enter a width for the ribbons in the Width expression field; click the Replace Expression button () to select a predefined expression to replace the current expression, or press Ctrl+Space to insert a predefined expression (SI unit: m). The default is 1 m. Select the Width scale factor check box to enter a user-defined scaling of the ribbons’ width in the associated field. By default, the program scales the width automatically.
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If Ribbon is selected for particle trajectories, specify a direction for the ribbons: At Ribbon direction, click the Replace Expression button () to select a predefined expression to replace the current expression, or press Ctrl+Space to insert a predefined expression (SI unit: m). You can also edit the expressions in the Direction, x-component; Direction, y-component; and Direction, z-component fields. Select the Width scale factor check box to enter a user-defined scaling of the ribbons’ width in the associated field. By default, the program scales the width automatically.
In Particle Trajectories plots, you can also choose an interpolation from the Interpolation list: None (the default) or Uniform. For the uniform interpolation, specify the Number of interpolated times (default value: 100).
For line plots where you specify the line width, enter a line Width or use the slider to select. The default, however, is Default from preferences, which takes the value, which is displayed in parentheses, from the Line width field in the Preferences dialog box, under Results>Plots>Graph Plots. If a line plot (graph plot) contains isolated data points (for example, in a logarithmic plot where parts of the data cannot be plotted), those data points follow the line width down to a minimum size for the points. Such isolated data points are replaced with line markers, if markers are used and plotted in the data points.
Plot Along Lines When Animating
If the plan is to create an Animation report, select the Plot along lines when animating check box. This is useful for Particle Trajectories, Particle Tracing, Particle Tracing with Mass, and Point Trajectories plots.
Point Motion
Select a Point motion to specify what should happen When particles leaves domain: Stick to boundary (to plot the points on the boundary at the exit point) or Disappear (to not render these points at all).
For static fields, specify the End time in the Advanced section. It is possible that all particles have left the domain at the selected time. In that case, all points appear at the outflow boundary if Stick to boundary is selected, and no points appear if Disappear is selected. To make the points appear, specify an earlier end time.
Point Radius
Enter a Point radius expression; click the Replace Expression button () to select a predefined expression to replace the current expression, or press Ctrl+Space to insert a predefined expression (SI unit: m). The default is 1 mm.
Point Style
Under Point style, select a Type: Point, None, Comet tail, Arrow, or Ellipse. If Point or Comet tail is selected, enter a Point Radius and Radius Scale Factor.
Comet tail and Arrow are available with the Particle Tracing, Particle Tracing with Mass, Particle Trajectories, Point Trajectories, and Ray Trajectories plots. All of them except Point Trajectories and Ray Trajectories require a license for the Particle Tracing Module. See Particle Tracing, Particle Tracing with Mass, Particle Trajectories, and Point Trajectories. The Ray Trajectories plot requires a license for the Acoustics Module or the Ray Optics Module.
Ellipse is available with the Particle Trajectories, Point Trajectories, and Ray Trajectories plots in 3D.
Radius Scale Factor
Select the Radius scale factor check box to enter a scalar number for the scale factor for a tube radius in a line plot, for example.
Range Quotient
If Logarithmic is selected as the arrow length, enter a Range quotient, which is the ratio between the maximum arrow length and the arrow length below which no arrow is drawn. The default is 100.
Rounded End Caps
The Rounded end caps check box is selected by default to smoothen the transition using a hemispherical head when a 2D or 3D Line plot with Tube selected as the Line type uses a radius expression that varies along the length. Clear this check box if you, for example, want to show the cross-sectional variation along the length using an equivalent radius expression. This setting is also available for Tube Data plots created using the COMSOL API.
Scale Factor
Enter a Scale factor for the arrows using a positive scalar number in the field or by using the associated slider (for scale factors between 0 and 1).
Scaling
From the Scale list, choose Linear (the default), Linear symmetric, or Logarithmic. Select Linear symmetric to obtain a color range centered around zero for a color table or color gradient. This setting is useful for visualizing wave-like solutions with zero bias. Selecting Logarithmic can make it easier to interpret the results when plotting expressions that have value ranges that cover multiple magnitudes.
Tail and Tail Components
Define the length and direction of the comet tail as a vector expression. For the Tail expression, click the Replace Expression button () to insert a predefined expression into the Tail, x-component; Tail, y-component; and Tail, z-component (for 3D plots) fields. The expressions available are based on the physics interfaces used in the model. The default expressions (typically pt.nvx, p.nvy, and pt.nvz) represent the negative of the particle velocity.
Tail Scale Factor
Select the Tail scale factor check box to enter a scalar number between 0 and 1 or use the slider to select.
Type
Select Curve or Solid from the Type list for the type of histogram to plot when the Function list under Output is set to Discrete. Select Solid for filled histogram bins.
Wireframe
To plot only on the visualization mesh, select the Wireframe check box, and then click Plot (). This displays the surface plot as a triangular grid.