COMSOL 6.2 - Defining the Coloring and Style

Select (the default) to position the arrow’s tail at the arrow position, to position the arrow’s head at the arrow position, or to position the center of the arrow at the arrow position.

Select an :

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, 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 field (default: 100) determines the ratio between the smallest and largest values in the range of values for the logarithmic arrow length.

When or is selected as the , also specify the (default: 200).

Select the check box to enter a scalar number to scale the arrows or use the slider to select.

Select an : , , or . Also, for Arrow Volume, Arrow Surface, Arrow Line, Arrow Point, Point Trajectories, and Ray Trajectories plots, select 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 point style type in Point Trajectories and Ray Trajectories plots, you can select from the list to not display any arrows.

For surface and contour plots, for example, from the list select to use a (see Coloring) or select to use a single color from the list. You can also select to define a custom color from the colored list below (on Windows) or by clicking the button (on Linux and macOS) and then selecting a color from the color palette.

For arrows, and unless a subnode determines the arrow colors, select an arrow or select to define a custom color from the colored list below (on Windows) or by clicking the button (on Linux and macOS) and then selecting a color from the color palette.

For lines in graph plots, select a : , , , , , , , , , , , , or .

If you select , define a custom color from the colored list below (on Windows) or by clicking the button (on Linux and macOS) and then selecting a color from the color palette. Choose or enter a line as a positive integer, or use the slider to select. By default, the line width is set a the , with the width from the preference setting shown in parentheses (default: 1). You specify the default line width as a positive integer on the page under in the window.

If you select , 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 . Also, choose (7 colors) or (19 colors) from the list. Choosing 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 , the line and maker color is taken from the selected color theme.

For and subnodes, you can choose to use the color from the color theme or to define a custom color, or choose any of the predefined colors.

In the color palette that opens, you can choose from a number of basic colors, or click 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 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.

The check box is selected by default. Click to clear the check box if required. The legend position is determined by the settings in the 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.

Choose one of the following options from the list:

With the and settings you can select the 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 field or the associated slider to define a parameter value between −1.5 and 1.5. The setting is mainly useful when is 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.

For plots, choose (the default) or from the list. If you chose , specify the number of discrete color bands in the field (default: 10).

Select a : (default), , or .

If is selected, and if the default color table ( in most plots) is not suitable for the plot, try other options. See Selecting Color Tables for details.

If is selected, select a or to choose a different color. For Line plots in 2D and 3D, you can also choose to use the line color from the chosen color theme.

If is selected, define the coloring as a gradient between two colors, which you specify from the and lists.

Select the check box to reverse the order of the colors in the color table (if is set to ).

Select the check box to reverse the order of the colors in the color gradient (if is set to ).

	Selecting Color Tables

Define the semi-major and semi-minor axes of the ellipse using vector expressions. For the and , click the 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.

Define the entry method for an ellipse as the point type from the : Choose to enter a , or choose to enter a number times in the field.

Select the check box to enter a scalar or use the slider to select.

Available for Point Graph and Global 1D plots, you can choose (the default) or from the list. Choose to plot global and point graphs as discrete values.

Select the 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.

In a Table Surface plot, choose (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 to treat the samples as discrete and draw them as large pixels.

Select a : (the default), , , or . If , , or is selected, also choose a for the grid.

For the plot (available with the Fatigue Module), you can select the check box to add a grid to the matrix histogram. Choose a color (default: gray) for the grid from the list.

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 list, select for no interpolation (the default), or select to use a uniform interpolation of the data using additional interpolated times defined in the field. The default is 100 interpolated times.

	Interpolation of lines is only available for Particle Trajectories plots, which are available for use with Particle datasets created with the Particle Tracing Module.

For contour, isosurface, and directivity plots, the list is available. You can choose (the default for contour and directivity plots; not available for isosurfaces), for a filled (joined) legend, or (the default for isosurface plots), for a legend with separated lines for the levels. The setting provides a filled legend for filled contours and a line legend for line and tube contours.

	For isosurface plots using interactive levels, only legends with lines are applicable, and the Legend type is then not available.

Select a type: , , , , , , , , , , or .

If a marker is selected (excluding ), then from the list, select (the default) or or (for Line Graph, Radiation Pattern, and Through Thickness plots) . For , enter the of markers to display (the default is 8; the maximum is 10,000 markers) or use the slider to select. If is selected, the markers appear in the data points for the plot (which for a plot of a 1D solution are the mesh nodes).

	The line markers are only available for Histogram plots using a continuous function.

	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.

The line styles available depend on the type of plot and the space dimension and include these options:

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From the list (for line graphs and point graphs, for example): , , , , , or . If you select , 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 .

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From the or list (for line, streamline, and particle trajectory plots, for example): , , or ( is not available for Line plots). For 3D Streamline, Particle Trajectories, Point Trajectories, and Ray Trajectories plots, is also available. Ribbons are an alternative to tubes for visualization of, for example, the vorticity of a flow field.

If is selected, enter a (the radius of the tube); click the 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.

If is selected for streamlines, enter a width for the ribbons in the field; click the 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 check box to enter a user-defined scaling of the ribbons’ width in the associated field. By default, the program scales the width automatically.

If is selected for particle trajectories, specify a direction for the ribbons: At , click the 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 ; ; and fields. Select the 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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In Particle Trajectories plots, you can also choose an interpolation from the list: (the default) or . For the uniform interpolation, specify the (default value: 100).

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For line plots where you specify the line width, enter a line or use the slider to select. The default, however, is , which takes the value, which is displayed in parentheses, from the field in the dialog box, under . 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.

If the plan is to create an report, select the check box. This is useful for Particle Trajectories, Particle Tracing, Particle Tracing with Mass, and Point Trajectories plots.

Select a to specify what should happen : (to plot the points on the boundary at the exit point) or (to not render these points at all).

For static fields, specify the in the 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 is selected, and no points appear if is selected. To make the points appear, specify an earlier end time.

Enter a ; click the 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.

Under , select a : , , , , or . If or 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. Comet tail plots provide a convenient way to indicate the direction of travel of particles at a given point in time. The tail of the comet typically points in the opposite direction to the particle velocity; visually, it is the same as the tail of a comet approaching the sun. These additional settings are available when Comet tail is selected: Tail and Tail Components and Tail Scale Factor. Ellipse is available with the Particle Trajectories, Point Trajectories, and Ray Trajectories plots in 3D. Ellipses provide a convenient way to visualize the polarization of rays. The eccentricity of the ellipse indicates the degree to which it is linearly or circularly polarized. For elliptical and circular polarization, arrows on the perimeter of the ellipse can be used to distinguish between left- and right-handed polarization.

Select the check box to enter a scalar number for the scale factor for a tube radius in a line plot, for example.

If is selected as the arrow length, enter a , which is the ratio between the maximum arrow length and the arrow length below which no arrow is drawn. The default is 100.

The check box is selected by default to smoothen the transition using a hemispherical head when a 2D or 3D plot with selected as the 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 plots created using the COMSOL API.

Enter a for the arrows using a positive scalar number in the field or by using the associated slider (for scale factors between 0 and 1).

From the list, choose (the default), , or . Select 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 can make it easier to interpret the results when plotting expressions that have value ranges that cover multiple magnitudes.

Define the length and direction of the comet tail as a vector expression. For the , click the button (

) to insert a predefined expression into the ; ; and (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.