The SEDRIS Data Representation Model
APPENDIX A - Classes
Relative Time Interval

Class Name: Relative Time Interval

Superclass - <Time Interval>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies an interval of time, defined by a start time and a stop time that are relative to another time.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

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

Example

  1. The time period for which a SEDRIS transmittal should be considered to be valid. The stop time can be considered to be an "expiration date".

FAQs

What is the purpose of this class?

This class provides a means to specify a time interval in terms of times relative to another time. The time interval is used to specify [CSDGM]-compliant metadata that describes the time period within which a high-level SEDRIS object (e.g. <Transmittal Root>, <Model>, <Image>, etc.) and as a general-purpose mechanism for describing time intervals. <Relative Time Interval> allows potential users of a SEDRIS transmittal to evaluate the time period covered by the transmittal or object, without necessarily having to actually obtain or examine the transmittal or object directly.

How can a data provider specify a time interval relative to start of simulation?

Do not include the component <Absolute Time Point>. If there is no component <Absolute Time Point>, the deltas are relative to simulation start.

Constraints

Composed of (two-way)

Component of (two-way)(inherited)

Inherited Field Elements

SE_Time_Significance time_significance; (notes)

Field Elements

SE_Integer delta_start_days;
SE_Integer delta_stop_days;
SE_Byte_Unsigned delta_start_hours; (notes)
SE_Byte_Unsigned delta_stop_hours; (notes)
SE_Byte_Unsigned delta_start_minutes; (notes)
SE_Byte_Unsigned delta_stop_minutes; (notes)
SE_Long_Float delta_start_seconds; (notes)
SE_Long_Float delta_stop_seconds; (notes)

Notes

Composed of Notes


Absolute_Time_Point

 If the given <Relative Time Interval> instance R has an
 <Absolute Time Point> component, R is relative to the
 specified absolute time; otherwise, R is relative to
 "simulation start" - that is, the start time of the
 consuming application.

Fields Notes


time_significance

 This indicates the significance of the time information.

delta_start_hours

 This shall be between 0 and 23.

delta_stop_hours

 This shall be between 0 and 23.

delta_start_minutes

 This shall be between 0 and 59.

delta_stop_minutes

 This shall be between 0 and 59.

delta_start_seconds

 This shall be between 0.0 and 59.0.

delta_stop_seconds

 This shall be between 0.0 and 59.0.
Prev: Regular Feature Face. Next: Relative Time Point. Up:Index.

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