COMSOL Multiphysics™

Ellipse
Ellipse
Supported Versions 0
Subtype of
Fields
Manifold
The class is defined by the following fields
ENTITY/
OBJECT
VARIABLE
DESCRIPTION
integer
Version
integer d Space dimension
Transform
Transformation class
double[d] center Center coordinate
boolean
Equal to 1 if clockwise rotation (only if d==2)
double[d] normal Normal vector coordinates,
double[d] M Major axis
double rat Ratio of minor axis length to major axis length
double offset Parameter at the end of major axis
boolean
Equal to 1 if ellipse is degenerated
Description
This manifold defines an ellipse in the two or three dimensional space.
In 2D, an ellipse is defined by a center point center, a vector defining the major
axis M of the ellipse (including the magnitude of the major axis), the radius ratio of
the minor axis length to the major axis length rat, the direction of the ellipse, and
the parameter offset at the major axis offset.
In 3D, an ellipse is defined by a center point center, a unit vector normal to the
plane of the ellipse normal, a vector defining the major axis of the ellipse M
(including the magnitude of the major axis), the radius ratio, and the parameter
offset at the major axis offset. The direction of the ellipse is defined by the right
hand rule using the normal vector.
An ellipse is a closed curve that has a period of 2π. It is parameterized as:
point = center + M cos(t - offset) + N sin(t - offset)
where M and N are the major and minor axes respectively.
Example
7 Ellipse # class
0 0 # version
2 # sdim
0 2 1 # transformation
0 0 # center
440 | CHAPTER 3: THE COMSOL MULTIPHYSICS FILES