The SEDRIS Data Representation Model
APPENDIX A - Classes
Feature Node

Class Name: Feature Node

Superclass - <Feature Topology>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class is a zero-dimensional <Feature Topology> instance specifying the location of a <Point Feature> instance and / or the endpoints of one or more <Feature Edge> instances.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

Example

  1. The location of a small building might be represented by a single <Feature Node>.

  2. The intersection of two roads would be represented by a <Feature Node>.

FAQs

When are <Feature Node> instances required?

<Feature Node> instances are required whenever either <Point Feature> or <Feature Edge> instances are present, regardless of the feature topology level.

Are there any geometric constraints on the <Location> that is associated with a <Feature Node>?

Yes. At all feature topology levels greater than zero, different <Feature Node> instances cannot share the same <Location>.

Constraints

Associated with (two-way)

Composed of (two-way) (inherited)

Composed of (two-way)

Component of (two-way) (inherited)

Inherited Field Elements

This class has no inherited field elements.

Notes

Associated with Notes


Feature_Edge

 The collection of <Feature Edge> instances that are connected
 to the <Feature Node>, if any.

Feature_Face

 This identifies the <Feature Face> instance that contains the
 given <Feature Node> instance, if one exists.

Feature_Volume

 The <Feature Volume> instance that contains the given
 <Feature Node> instance, if any.

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Last updated: July 16, 2004 Copyright © 2004 SEDRIS