UnionSelection, IntersectionSelection, DifferenceSelection, ComplementSelection

Combine selections of entities or objects using a Boolean operation.

Syntax

model.geom(<tag>).create(<ftag>,"UnionSelection");

model.geom(<tag>).create(<ftag>,"IntersectionSelection");

model.geom(<tag>).create(<ftag>,"DifferenceSelection");

model.geom(<tag>).create(<ftag>,"ComplementSelection");

model.geom(<tag>).feature().set(property,<value>);

model.geom(<tag>).feature().getType(property);

Description

Use UnionSelection to get all entities/objects that belong to at least one of the input selections. Use IntersectionSelection to get all entities/objects that belong to all input selections. Use DifferenceSelection to get all entities/objects that belong some of the add selections, but do not belong to any of the subtract selections. Use ComplementSelection to get all entities/objects of the given dimension that do not belong to any input selection.

For DifferenceSelection, the following properties are available:

Property	Value	Default	Description
add	String[]	{}	Tags of selections to add.
entitydim	-1 | 0 | 1 | 2 | 3	space dimension	Dimension of entities to select. -1 means Object.
subtract	String[]	{}	Tags of selections to subtract.
selkeep	on | off	on	Keep the selection within the geometry sequence.
selshow	on | off	on	Show selection in physics, materials, and so on; in part instances; or in 3D from a plane geometry.
contributeto	String	none	Tag of cumulative selection to contribute to.

For the other selections, the following properties are available:

Property	Value	Default	Description
entitydim	-1 | 0 | 1 | 2 | 3	space dimension	Dimension of entities to select. -1 means Object.
input	String[]	{}	Tags of input selections.
selkeep	on | off	on	Keep the selection within the geometry sequence.
selshow	If the level is not Object, the allowed values are on | off. If the level is Object, the allowed values are all | obj | dom | bnd | edg | pnt | off.	If the level is not Object, the default value is on. If the level is Object, the default value is all in a component’s geometry, obj in a part, and dom in a work plane’s Plane Geometry.	Show selection in physics, materials, and so on; in part instances; or in 3D from a plane geometry. obj is not available in a component’s geometry.
contributeto	String	none	Tag of cumulative selection to contribute to.

See Selections of Geometric Entities for general information about selections.

Example

In an array of blocks, select all vertices whose distance to the origin is between 2.5 and 3.5. This results in 22 vertices in 7 different objects.

Code for use with Java

Model model = ModelUtil.create("Model");

GeomSequence g = model.geom().create("geom1", 3);

g.create("blk1", "Block");

g.create("arr1", "Array");

g.feature("arr1").selection("input").set("blk1");

g.feature("arr1").set("size", new int[]{3,3,1});

g.feature("arr1").set("displ", new double[]{1.5,1.5,0});

g.run("arr1");

g.create("ballsel1","BallSelection");

g.feature("ballsel1").set("entitydim", 0);

g.feature("ballsel1").set("r", 3.5);

g.feature().duplicate("ballsel2","ballsel1");

g.feature("ballsel2").set("r", 2.5);

g.create("difsel1", "DifferenceSelection");

g.feature("difsel1").set("entitydim", 0);

g.feature("difsel1").set("add", new String[]{"ballsel1"});

g.feature("difsel1").set("subtract", new String[]{"ballsel2"});

g.run("difsel1");

String[] obj = g.selection("difsel1").objects();

int nVtx = 0;

for (int i=0; i<obj.length; ++i)

  nVtx += g.selection("difsel1").entities(obj[i],0).length;

// obj.length = 7, nVtx = 22

Code for use with MATLAB

model = ModelUtil.create('Model');

g = model.geom.create('geom1', 3);

g.create('blk1', 'Block');

g.create('arr1', 'Array');

g.feature('arr1').selection('input').set('blk1');

g.feature('arr1').set('size', [3,3,1]);

g.feature('arr1').set('displ', [1.5,1.5,0]);

g.run('arr1');

g.create('ballsel1','BallSelection');

g.feature('ballsel1').set('entitydim', 0);

g.feature('ballsel1').set('r', 3.5);

g.feature.duplicate('ballsel2','ballsel1');

g.feature('ballsel2').set('r', 2.5);

g.create('difsel1', 'DifferenceSelection');

g.feature('difsel1').set('entitydim', 0);

g.feature('difsel1').set('add', {'ballsel1'});

g.feature('difsel1').set('subtract', {'ballsel2'});

g.run('difsel1');

obj = g.selection('difsel1').objects;

nVtx = 0;

for i=1:length(obj)

  nVtx = nVtx + length(g.selection('difsel1').entities(obj(i),0));

end

% length(obj) = 7, nVtx = 22

See Also

AdjacentSelection, BallSelection, BoxSelection, CylinderSelection, ExplicitSelection