The SEDRIS Data Representation Model
APPENDIX A - Classes
Absolute Time

Class Name: Absolute Time

Superclass - <Time Point>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies an absolute time (that is, Greenwich Mean Time (GMT), which is not relative to some other point in time).

<Absolute Time> provides

  1. a means to specify an absolute time (GMT) for metadata, and
  2. a general-purpose mechanism for describing points in absolute (GMT) 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. Consider a SEDRIS transmittal constructed from a historical database, in which the time at which an event happened is recorded as Oct 3 17:56:47 GMT 1994. In the SEDRIS transmittal, this information is specified by an <Absolute Time> instance with time_significance = SE_TIME_SIGNIF_OCCURRENCE, as follows.

    time_significance = SE_TIME_SIGNIF_OCCURRENCE
    time_value. value.ymd_hms. year =1994
    time_value. value.ymd_hms. month = SE_MONTH_OCTOBER
    time_value. value.ymd_hms. day_of_month =3
    time_value. value.ymd_hms. hour =17
    time_value. value.ymd_hms. minutes =56
    time_value. value.ymd_hms. seconds =47.0

  2. Consider a SEDRIS transmittal for which the data provider wishes to represent the date and time when the transmittal was created - in this example, Mar 23 15:18:33 GMT 2003. In this case, the data provider would create an <Absolute Time> instance with time_significance = SE_TIME_SIGNIF_CREATION_DATE and the other field values set appropriately, as follows.

    time_significance = SE_TIME_SIGNIF_CREATION_DATE
    time_value. configuration = SE_TIME_CFG_DATE_YMD_AND_TIME_HMS
    time_value. value.ymd_hms. year =2003
    time_value. value.ymd_hms. month = SE_MONTH_MARCH
    time_value. value.ymd_hms. day_of_month =23
    time_value. value.ymd_hms. hour =15
    time_value. value.ymd_hms. minutes =18
    time_value. value.ymd_hms. seconds =33.0

    This <Absolute Time> instance would then be attached as a component of the transmittal's <Transmittal Root>.

  3. The date and time of observations.

FAQs

No FAQs supplied.

Constraints

Component of (two-way) (inherited)

Component of (two-way)

Inherited Field Elements

SE_Time_Significance time_significance; (notes)

Field Elements

SE_Time_Value time_value; (notes)

Notes

Fields Notes


time_significance

 The time_significance field specifies the significance of
 the time information.

time_value

 The time_value field specifies the time value.
Next: Absolute Time Interval. Up:Index.

Last updated: July 16, 2004 Copyright © 2004 SEDRIS™