Cut Point 1D, Cut Point 2D, and Cut Point 3D
Use a Cut Point 1D (), Cut Point 2D (), or Cut Point 3D () dataset to plot and evaluate a value in certain points along time or along a parametric solution and to create cross-sectional point plots. The choice of 1D, 2D, or 3D only controls the type of input the dataset accepts. For example, a Cut Point 1D can only be added to 1D datasets and a Cut Point 2D can only be added to 2D datasets. Any of these can be used to make a point graph plot along time and so forth and for point evaluations.
Add a Cut Point 1D dataset for points as cross-section data. Add a Cut Point 2D or Cut Point 3D dataset to, for example, plot the values in certain points along time or along a parametric solution and use the dataset in its original dimension. Useful ways to visualize and display data in cut points are through Point Evaluation nodes () under Derived Values and Point Graph nodes () under 1D Plot Group nodes.
Go to Common Results Node Settings for links to information about the Data section.
Point Data
To specify the point data coordinates using the Entry method list:
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Select Coordinates (the default) to enter the coordinates. For Cut Point 1D, enter x coordinates; for Cut Point 2D, enter x and y coordinates; and for Cut Point 3D enter x, y, and z coordinates.
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Select From file to enter or browse to a text file with the cut point data. Enter the path and filename in the Filename field, or click Browse () to browse to the file using the Coordinate File window that opens. You can also click the downward arrow beside the Browse button and choose Browse From () to open the fullscreen Select File window. Click the downward arrow for the Location menu () to choose Show in Auxiliary Data () to move to the row for this file in the Auxiliary Data window, Copy Location (), and (if you have copied a file location) Paste Location (). You can use text files (*.txt) or, if the license includes LiveLink™ for Excel®, Microsoft Excel Workbook files (*.xlsx). The file format is such that each row contains N coordinates for an N-dimensional cut point. That is, each row contains coordinate values like the following example, for a 3D case:
x0 y0 z0 …
x1 y1 z1 …
…
For text files, you can use any of the following characters to separate the coordinates: space, comma, semicolon, or a tab character. Empty lines and lines that begin with a percent (%) character are ignored.
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Select Grid to enter grid coordinates for gridded data. For Cut Point 1D, enter x coordinates; for Cut Point 2D, enter x and y coordinates; and for Cut Point 3D, enter x, y, and z coordinates.
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Select Regular grid to specify the number of points in each direction. Enter Number of x points, Number of y points (Cut Point 2D and 3D), and Number of z points (Cut Point 3D only). The default value is 10 points in each direction.
From the Snapping list, choose None for no snapping (the default), Snap to closest boundary to snap the selected points to the closest boundary in the geometry, or Snap to closest edge (Cut Point 3D only) to snap the selected points to the closest edge in the geometry. Use this option when evaluating a variable that is available on boundaries but not in domains, for example. Otherwise, leave the snapping off (the default setting, None) to avoid the additional computational cost.
Through-Thickness Location
This section is only available for Cut Point 3D datasets that refer to a Layered Material dataset and where Snapping is set to Snap to closest boundary or Snap to closest edge.
Select a Location definition: Reference surface (the default), Physical, or Relative.
Once Reference surface is selected, the through-thickness location is taken from a layered material definition specified in a Layered Material Link, Layered Material Stack, or Material node (defined as a single-layer material) under Materials.
Enter one or more values for a Local z-coordinate for the Physical option or Local z-coordinate [-1,1] for the Relative option. The bottom, middle, and top through-thickness location of a layered material, having a total thickness d, can be defined as follows:
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Bottom: 0 (Physical) or −1 (Relative)
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Middle: d/2 (Physical) or 0 (Relative)
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Top: d (Physical) or 1(Relative)
Click the Range button () to define a range of local z-coordinates using the Range dialog box.
Advanced
By default, the Cut Point datasets create a point number variable so that you can refer to that variable in a Point Graph, for example, where you want to plot some quantity at those cut points. The default variable name is typically cpt1n, for the first Cut Point dataset. Enter another variable name in the Point number variable field if desired.
For a Cut Point 1D example, and if you have the Plasma Module, see Benchmark Model of a Capacitively Coupled Plasma: Application Library path Plasma_Module/Capacitively_Coupled_Plasmas/ccp_benchmark.
For a Cut Point 2D example, see Steady-State 2D Heat Transfer with Conduction: Application Library path COMSOL_Multiphysics/Heat_Transfer/heat_convection_2d.
For a Cut Point 3D example, and if you have the:
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MEMS Module, see Prestressed Micromirror: Application Library path MEMS_Module/Actuators/micromirror.
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Microfluidics Module, see Star-Shaped Microchannel: Application Library path Microfluidics_Module/Fluid_Flow/star_chip.
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RF Module, see Microwave Oven: Application Library path RF_Module/Microwave_Heating/microwave_oven.