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cellEdges

Find edges belonging to boundaries of specified cells

    Description

    example

    EdgeID = cellEdges(g,RegionID) finds edges belonging to the boundaries of the cells with ID numbers listed in RegionID.

    example

    EdgeID = cellEdges(g,RegionID,FilterType) returns internal, external, or all edges belonging to the boundaries of the cells with ID numbers listed in RegionID.

    Examples

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    Find edges belonging to the boundaries of the two middle cylinders in a geometry consisting of four stacked cylinders.

    Create a geometry that consists of four stacked cylinders.

    gm = multicylinder(5,[1 2 3 4],"ZOffset",[0 1 3 6])
    gm = 
      DiscreteGeometry with properties:
    
           NumCells: 4
           NumFaces: 9
           NumEdges: 5
        NumVertices: 5
           Vertices: [5x3 double]
    
    

    Plot the geometry with the cell and edge labels.

    pdegplot(gm,"CellLabels","on","EdgeLabels","on","FaceAlpha",0.2)

    Figure contains an axes object. The axes object contains 3 objects of type quiver, patch, line.

    Find edges belonging to the boundaries of cells 2 and 3.

    edgeIDs = cellEdges(gm,[2 3])
    edgeIDs = 1×3
    
         2     3     4
    
    

    Find edges belonging to the boundaries of the outer cuboid in a geometry consisting of two nested cuboids.

    Create a geometry that consists of two nested cuboids of the same height.

    gm = multicuboid([2 5],[4 10],3)
    gm = 
      DiscreteGeometry with properties:
    
           NumCells: 2
           NumFaces: 12
           NumEdges: 24
        NumVertices: 16
           Vertices: [16x3 double]
    
    

    Plot the geometry with the cell labels.

    pdegplot(gm,"CellLabels","on","FaceAlpha",0.2)

    Figure contains an axes object. The axes object contains 3 objects of type quiver, patch, line.

    Find all edges belonging to the boundaries of the outer cell. Show the first 10 edges.

    edgeIDs = cellEdges(gm,2);
    edgeIDs(1:10)
    ans = 1×10
    
         1     2     3     4     5     6     7     8     9    10
    
    

    From all edges belonging to the boundaries of the outer cell, return the edges belonging to only the internal faces. Internal faces are faces shared between multiple cells.

    edgeIDs_int = cellEdges(gm,2,"internal")
    edgeIDs_int = 1×4
    
         9    10    11    12
    
    

    From all edges belonging to the boundaries of the outer cell, return the edges belonging to the external faces. Show the first 10 edges.

    edgeIDs_ext = cellEdges(gm,2,"external");
    edgeIDs_ext(1:10)
    ans = 1×10
    
         1     2     3     4     5     6     7     8    13    14
    
    

    Input Arguments

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    3-D geometry, specified as a DiscreteGeometry object.

    Cell ID, specified as a positive number or a vector of positive numbers. Each number represents a cell ID.

    Type of edges to return, specified as "internal", "external", or "all". Depending on this argument, cellEdges returns these types of faces:

    • "internal" — Edges belonging to only internal faces. Internal faces are faces shared between multiple cells.

    • "external" — Edges belonging to only external faces. External faces are faces not shared between multiple cells.

    • "all" — All edges belonging to the specified cells.

    Output Arguments

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    IDs of edges belonging to boundaries of specified cells, returned as a positive number or a vector of positive numbers.

    Version History

    Introduced in R2021a