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TriangleGetSegmentMarkers[expr]

returns the segment markers for a Triangle expression.

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TriangleLink`
TriangleLink`

TriangleGetSegmentMarkers

TriangleGetSegmentMarkers[expr]

returns the segment markers for a Triangle expression.

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Examples

Basic Examples  (1)

First, load the package:

Wolfram Language code: Needs["TriangleLink`"]

This creates an instance of a Triangle expression:

Wolfram Language code: inst = TriangleCreate[]

This sets up points and facets to use:

Wolfram Language code: pts = {{0., 0.}, {2., 0.}, {2., 2.}, {0., 1.}}; segments = {{1, 2}, {2, 3}, {3, 4}, {4, 1}};

This sets the points and facets in the Triangle instance:

Wolfram Language code: TriangleSetPoints[inst, pts]; TriangleSetSegments[inst, segments];

This sets the point and segment markers:

Wolfram Language code: TriangleSetPointMarkers[inst, {43, 43, 66, 66}]; TriangleSetSegmentMarkers[inst, {43, 2, 66, 3}];

This carries out the triangulation, returning a new Triangle instance:

Wolfram Language code: outInst = TriangleTriangulate[ inst, "pqa0.1"]

This extracts the points and elements from the triangulation:

Wolfram Language code: coords = TriangleGetPoints[outInst]; meshElements = TriangleGetElements[outInst];

With the following support function, you can visualize the triangles:

Wolfram Language code: TriangleWireframe[i_] := Line[ Flatten[ i[[All, #]]& /@ {{1, 2}, {2, 3}, {3, 1}}, 1]]
Wolfram Language code: Graphics[GraphicsComplex[coords, TriangleWireframe[meshElements]]]

This extracts the segment markers:

Wolfram Language code: segmentMarkers = TriangleGetSegmentMarkers[outInst]

Visualize some of the surface points:

Wolfram Language code: selectedPoints = {43, 66} Graphics[GraphicsComplex[ coords, Line /@ Pick[TriangleGetSegments[outInst], segmentMarkers, #] ]& /@ selectedPoints]