The SEDRIS Data Representation Model
APPENDIX A - Classes
Feature Representation

Abstract Class Name: Feature Representation

Superclass - <SEDRIS Abstract Base>

Subclasses

Definition

An instance of this DRM class represents an entity in the environment, or an organized collection of such entities, that specifies the properties of the entity in terms of its spatial connectivity.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

Example

  1. A wide variety of spatially located entities, including roads, railroads, streams, rivers, lakes, bridges, buildings, built-up areas, forests, fields, political boundaries, powerlines, and airfields can be abstractly represented as <Feature Representation> instances. <Feature Representation> instances may be organized into thematic layers, if desired.

FAQs

Are there any limits on the size of a feature?

No. <Feature Representation> instances are conceptual entities. There are no limits on the size of a single feature, and very few limits on what can be considered to be a single feature. For example, the entire Interstate highway system of the United States could be considered to be a single high-level feature, if that were useful in a particular context. However, there are some limits on individual <Primitive Feature> instances.

Constraints

Associated to (one-way)

Associated by (one-way)

Composed of (two-way)

Composed of (two-way metadata)

Component of (two-way)

Inherited Field Elements

This class has no inherited field elements.

Notes

Associated to Notes


Feature_Representation

An association between two <Feature Representation> instances indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <Base Association Data> link object on the association relationship.


Geometry_Hierarchy

An association between a <Geometry Hierarchy> instance and a <Feature Representation> instance indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <Base Association Data> link object on the association relationship.


Property_Grid

An association between a <Property Grid> instance and a <Feature Representation> instance indicates that the environmental object(s) represented by the <Feature Representation> instance and the <Property Grid> instance (or some specific cell data within that <Property Grid> instance) have the semantic relationship indicated by the <Base Association Data> link object on the association relationship. Each associated <Property Grid> instance indicates whether the entire <Property Grid> instance or only some specific cell data within it is participating in the relationship in question.

Associated from Notes


Feature_Representation

An association between two <Feature Representation> instances indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <Base Association Data> link object on the association relationship.


Geometry_Hierarchy

An association between a <Geometry Hierarchy> instance and a <Feature Representation> instance indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <Base Association Data> link object on the association relationship.


Property_Grid

An association between a <Property Grid> instance and a <Feature Representation> instance indicates that the environmental object(s) represented by the <Feature Representation> instance and the <Property Grid> instance (or some specific cell data within that <Property Grid> instance) have the semantic relationship indicated by the <Base Association Data> link object on the association relationship. Each associated <Property Grid> instance indicates whether the entire <Property Grid> instance or only some specific cell data within it is participating in the relationship in question.


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Last updated: July 26, 2006 Copyright © 2006 SEDRIS