The SEDRIS Data Representation Model
APPENDIX A - Classes
Elliptic Cylinder

Class Name: Elliptic Cylinder

Superclass - <Volume Geometry>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies a closed cylindrical volume that has an elliptical rather than circular cross-section. The elliptic end faces are determined by the major and minor axes and two component <Reference Vector> instances. The component <Location 3D> locates the centre of the bottom face. The first component <Reference Vector> (vector_type = SE_REF_VEC_TYP_MAJOR_AXIS) gives the direction of the major axis. The second component <Reference Vector> (vector_type = SE_REF_VEC_TYP_FACE_NORMAL) defines the normal direction to the plane of the bottom <Ellipse> and the direction of the Z-axis, and shall be perpendicular to the major axis <Reference Vector>.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

Example

  1. The physical extent of certain underwater acoustic phenomena such as cold water eddies and fish schools are best described by <Elliptic Cylinder> instances.

FAQs

No FAQs supplied.

Constraints

Associated with (two-way)

Composed of (two-way)(inherited)

Composed of (two-way)

Composed of (two-way metadata)(inherited)

Component of (two-way)(inherited)

Inherited Field Elements

This class has no inherited field elements.

Field Elements

SE_Long_Float major_axis_length; (notes)
SE_Long_Float minor_axis_length; (notes)
SE_Long_Float height; (notes)

Notes

Associated with Notes


Geometry_Node

 This corresponds to the centre of the given <Elliptic Cylinder>
 instance.

Composed of Notes


Union_Of_Primitive_Geometry

 A <Primitive Geometry> contains a <Union Of Primitive Geometry>
 instance as a component only when that <Primitive Geometry>
 can be decomposed into nested <Primitive Geometry>, as (for
 example) a <Polygon> can be decomposed into subfaces.

Location

 This is the location of the centre of the given
 <Elliptic Cylinder> instance.

Reference_Vector

 These are the elliptic cross section axes.

 The first component <Reference Vector> specifies the major
 axis direction with vector_type = SE_REF_VEC_TYP_MAJOR_AXIS.

 The second component <Reference Vector> specifies the major
 axis direction with vector_type = SE_REF_VEC_TYP_MINOR_AXIS.

Fields Notes


major_axis_length

 This is in metres > 0.0.

minor_axis_length

 This is in metres > 0.0.

height

 This is in metres > 0.0.

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Last updated: May 15, 2003 Copyright © 2003 SEDRIS™