The SEDRIS Data Representation Model
APPENDIX A - Classes
Enumeration Axis

Class Name: Enumeration Axis

Superclass - <Axis>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class is an <Axis> that uses EDCS Enumerant Codes rather than numerical values as hash marks.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

This class appears on only one page of the DRM class diagram.

Example

  1. Consider a <Property Grid> instance containing data that varies by ocean bottom material composition. The <Property Grid> instance therefore has an <Enumeration Axis> component of axis_type = EAC_WATER_BODY_FLOOR_MATERIAL_TYPE. The axis_value_array[] contains corresponding values such as EEC_WTRBDFLRMATTY_CLAY_AND_SILT.

  2. Consider a <Property Table> instance containing data that varies by season of the year. The <Property Table> instance therefore has an <Enumeration Axis> component of axis_type = EAC_SEASON. The axis_value_array[] contains some or all of the values: EEC_SEASON_WINTER, EEC_SEASON_SPRING, EEC_SEASON_SUMMER, or EEC_SEASON_AUTUMN.

FAQs

How should a data provider decide between using an <Enumeration Axis> with one <Table Property Description> per axis entry, and using multiple <Table Property Description> instances, with each <Table Property Description> replacing a value on the <Enumeration Axis>?

If the values on the <Enumeration Axis> represent different values of some variable (days of the week, colours, seasons, states), the data provider should use an <Enumeration Axis> (request a new EAC enumeration if justified). Multiple <Table Property Description> instances should be used when the <Data Table> contains different kinds of dependent data, such as temperature, pressure, and humidity.

Constraints

Component of (two-way) (inherited)

Inherited Field Elements

EDCS_Attribute_Code axis_type; (notes)
SE_Short_Integer_Positive axis_value_count; (notes)

Field Elements

EDCS_Enumerant_Code axis_value_array[];

Notes

Fields Notes


axis_type

 The axis_type field specifies the property being described by the
 given <Axis> instance.

axis_value_count

 The axis_value_count field specifies the number of "hash marks"
 along the given <Axis> instance.
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Last updated: July 16, 2004 Copyright © 2004 SEDRIS™