COMSOL 6.2 - Tangent

Create a tangent line segment to one or two 2D edges.

model.component(<ctag>).geom(<tag>).create(<ftag>,"Tangent");

model.component(<ctag>).geom(<tag>).feature(<ftag>).selection(property);

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

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

model.component(<ctag>).geom(<tag>).feature(<ftag>).setAttribute(attribute,<value>);

model.component(<ctag>).geom(<tag>).feature(<ftag>).getAttribute(attribute);

Use model.component(<ctag>).geom(<tag>).create(<ftag>,"Tangent") to create a line segment tangent to two edges or tangent to one edge with a fixed endpoint. The following properties are available:

Table 3-165: Valid Property/Value Pairs for Tangent.
Property	Value	Default	Description
contributeto	String	none	Tag of cumulative selection to contribute to.
edge	Selection		Edge in a geometry object to find tangent to.
selresult	on \| off	off	Create selections of all resulting objects.
selresultshow	all \| obj \| bnd \| edg \| pnt \| off	bnd	Show selections, if selresult is on, 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. dom, bnd, and edg are not available in all features.
start	double	0.5	Start guess for parameter value of point of tangency.
type	edge \| point \| coord	edge	Type of tangent.

If type is edge a common tangent line to two edges are constructed. Then, the following additional properties are available:

Table 3-166: Valid Property/Value Pairs.
Property	Value	Default	Description
edge2	Selection		Second edge in some geometry object to find tangent to.
start2	double	0.5	Start guess for parameter value of point of tangency.

If type is point a tangent line through a given point is constructed. Then, the following additional property is available:

Table 3-167: Valid Property/Value Pairs.
Property	Value	Default	Description
point	Selection		Point in some geometry object.

If type is coord a tangent line through a point with given coordinates are constructed. Then, the following additional property is available:

Table 3-168: Valid Property/Value Pairs.
Property	Value	Default	Description
coord	double[]	{0,0}	Coordinates.

If a tangent cannot be found, a tangent to some adjacent edge is constructed, if possible.

For information about the selresult and contributeto properties, see Selections of Geometric Entities.

The following attributes are available:

Table 3-169: Valid attributes
Name	Value	Default	Description
construction	on \| off	off	Designate the resulting objects as construction geometry.

model.component(<ctag>).geom(gname).create(fname,"tangent") creates a Tangent feature.

The following properties are no longer supported:

Table 3-170: obsolete Property/Value Pairs.
Property name	property Value	Default	Description
edim1	0 \| 1	geometry dependent	Starting point element dimension: 0 for vertex, 1 for edge.
edim2	0 \| 1	geometry dependent	Ending point element dimension: 0 for vertex, 1 for edge.
dom1	integer	1	Starting point entity number.
dom2	integer	1	Ending point entity number.
out	cell array of Strings	{}	Additional output data.
start1	double	0.5	Starting point parameter value on specified edge.

The following sequence generates a tangent from the unit circle to the point (2, 0):

Code for Use with Java

Model model = ModelUtil.create("Model1");

model.component().create("comp1");

GeomSequence g = model.component("comp1").geom().create("geom1",2);

g.create("c1","Circle");

g.create("tan1","Tangent");

g.feature("tan1").set("type","coord");

g.feature("tan1").selection("edge").set("c1",3);

g.feature("tan1").set("coord","2 0");

Code for Use with MATLAB

model = ModelUtil.create('Model1');

model.component.create('comp1');

g = model.component('comp1').geom.create('geom1',2);

g.create('c1','Circle');

g.create('tan1','Tangent');

g.feature('tan1').set('type','coord');

g.feature('tan1').selection('edge').set('c1',3);

g.feature('tan1').set('coord','2 0');

The following sequence generates a common tangent between two circles:

Code for Use with Java

Model model = ModelUtil.create("Model1");

model.component().create("comp1");

GeomSequence g = model.component("comp1").geom().create("geom1",2);

g.create("c1","Circle");

g.create("c2","Circle");

g.feature("c2").set("pos", "2 2");

g.create("tan1","Tangent");

g.feature("tan1").selection("edge").set("c1",4);

g.feature("tan1").selection("edge2").set("c2",4);

Code for Use with MATLAB

model = ModelUtil.create('Model1');

model.component.create('comp1');

g = model.component('comp1').geom.create('geom1',2);

g.create('c1','Circle');

g.create('c2','Circle');

g.feature('c2').set('pos', '2 2');

g.create('tan1','Tangent');

g.feature('tan1').selection('edge').set('c1',4);

g.feature('tan1').selection('edge2').set('c2',4);