Standard representation of geographic point location by coordinates (ISO 6709:2008, including Cor 1:2009)

ISO 6709:2008 is applicable to the interchange of coordinates describing geographic point location. It specifies the representation of coordinates, including latitude and longitude, to be used in data interchange. It additionally specifies representation of horizontal point location using coordinate types other than latitude and longitude. It also specifies the representation of height and depth that can be associated with horizontal coordinates. Representation includes units of measure and coordinate order.
ISO 6709:2008 is not applicable to the representation of information held within computer memories during processing and in their use in registers of geodetic codes and parameters.
ISO 6709:2008 supports point location representation through the eXtensible Markup Language (XML) and, recognizing the need for compatibility with the previous version of this International Standard, ISO 6709:1983, allows for the use of a single alpha-numeric string to describe point locations.
For computer data interchange of latitude and longitude, ISO 6709:2008 generally suggests that decimal degrees be used. It allows the use of sexagesimal notations: degrees, minutes and decimal minutes or degrees, minutes, seconds and decimal seconds.
ISO 6709:2008 does not require special internal procedures, file-organization techniques, storage medium, languages, etc., to be used in its implementation.

Standarddarstellung für geographische Punkte durch Koordinaten (ISO 6709:2008, einschließlich Cor 1:2009)

Die vorliegende Internationale Norm ist auf den Austausch von Koordinaten anwendbar, die die Lage geographischer Punkte beschreiben. Sie legt die Darstellung von Koordinaten einschließlich geographischer Breite und Länge fest, die beim Datenaustausch zu verwenden sind. Außerdem legt sie die Lagedarstellung von horizontalen Punkten fest, bei der andere Koordinaten als Breitengrad und Längengrad verwendet werden. Ebenfalls festgelegt wird die Darstellung von Höhe und Tiefe, die Punkten mit Lagekoordinaten zugeordnet werden können. Diese Darstellung umfasst auch Maßeinheiten sowie die Reihenfolge der Koordinaten.
Diese Norm gilt nicht für die Darstellung von gespeicherten Informationen während der Datenverarbeitung und bei deren Anwendung in Registern von geodätischen Codes und Parametern.
Diese Internationale Norm unterstützt die Darstellung der Lage von Punkten durch die eXtensible Markup Language (XML), und da die Kompatibilität der vorliegenden Norm mit der früheren Fassung dieser Inter-nationalen Norm, ISO 6709:1983, erforderlich ist, darf auch eine einzelne alpha-numerische Zeichenkette (ein Textstring) verwendet werden, um Punkte zu beschreiben.
Für den Datenaustausch von Breitengrad und Längengrad zwischen Computern schlägt diese Internationale Norm allgemein vor, Dezimalgrad zu verwenden. Sie erlaubt auch die Verwendung sexagesimaler Notationen: Grad, Minuten und Dezimalminuten oder Grad, Minuten, Sekunden und Dezimalsekunden.
Diese Internationale Norm erfordert keine besonderen internen Abläufe, Dateiorganisationsmaßnahmen, Speichermedien, Programmiersprachen usw., die bei deren Implementierung anzuwenden sind.

Représentation normalisée des latitude, longitude et altitude pour la localisation des points géographiques (ISO 6709:2008, Cor 1:2009 inclus)

L'ISO 6709:2008 est applicable à l'échange des coordonnées décrivant la localisation de points géographiques. Elle spécifie la représentation des coordonnées, dont la latitude et la longitude, utilisées pour l'échange de données. En outre, elle spécifie la représentation de la localisation des points horizontaux en utilisant les types de coordonnées différents de la latitude et de la longitude. Elle spécifie aussi la représentation de la hauteur et de la profondeur qui peuvent être associées à des coordonnées horizontales. La représentation inclut l'ordre des unités de mesure et des coordonnées.
L'ISO 6709:2008 n'est pas applicable à la représentation des informations gardées dans les mémoires des ordinateurs pendant leur traitement et leur utilisation dans les enregistrements des codes et des paramètres géodésiques.
L'ISO 6709:2008 supporte la représentation de la localisation des points au moyen de XML (langage de balisage extensible) et, par respect de la nécessité de compatibilité avec l'édition précédente, l'ISO 6709:1983, elle permet l'utilisation d'une chaîne alphanumérique unique pour décrire la localisation des points.
Pour l'échange des données informatisées sur la latitude et la longitude, l'ISO 6709:2008 suggère généralement d'utiliser les fractions décimales de degrés. Elle permet l'utilisation des notations sexagésimales: les degrés, les minutes et les fractions décimales de minutes ou les degrés, les minutes, les secondes et les fractions décimales de secondes.
L'ISO 6709:2008 ne comporte pas d'exigences spécifiques concernant les procédures internes, les techniques d'organisation des fichiers, les moyens de sauvegarde, les langages, etc. pour sa mise en oeuvre.

Standardna predstavitev geografske točkovne lokacije s koordinatami (ISO 6709:2008, vključuje popravek Cor. 1:2009)

General Information

Status
Withdrawn
Publication Date
23-Jun-2009
Withdrawal Date
25-Oct-2022
Current Stage
9960 - Withdrawal effective - Withdrawal
Completion Date
26-Oct-2022

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SLOVENSKI STANDARD
SIST EN ISO 6709:2009
01-september-2009
6WDQGDUGQDSUHGVWDYLWHYJHRJUDIVNHWRþNRYQHORNDFLMHVNRRUGLQDWDPL ,62
YNOMXþXMHSRSUDYHN&RU

Standard representation of geographic point location by coordinates (ISO 6709:2008,

including Cor 1:2009)
Standarddarstellung für geographische Punkte durch Koordinaten (ISO 6709:2008,
einschließlich Cor 1:2009)

Représentation normalisée des latitude, longitude et altitude pour la localisation des

points géographiques (ISO 6709:2008, Cor 1:2009 inclus)
Ta slovenski standard je istoveten z: EN ISO 6709:2009
ICS:
35.040 Nabori znakov in kodiranje Character sets and
informacij information coding
SIST EN ISO 6709:2009 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 6709:2009
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SIST EN ISO 6709:2009
EUROPEAN STANDARD
EN ISO 6709
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2009
ICS 35.040
English Version
Standard representation of geographic point location by
coordinates (ISO 6709:2008, including Cor 1:2009)

Représentation normalisée des latitude, longitude et Standarddarstellung für geographische Punkte durch

altitude pour la localisation des points géographiques (ISO Koordinaten (ISO 6709:2008, einschließlich Cor 1:2009)

6709:2008, Cor 1:2009 inclus)
This European Standard was approved by CEN on 12 June 2009.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European

Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national

standards may be obtained on application to the CEN Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the

official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,

France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,

Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 6709:2009: E

worldwide for CEN national Members.
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SIST EN ISO 6709:2009
EN ISO 6709:2009 (E)
Contents Page

Foreword ..............................................................................................................................................................3

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SIST EN ISO 6709:2009
EN ISO 6709:2009 (E)
Foreword

The text of ISO 6709:2008, including Cor 1:2009 has been prepared by Technical Committee ISO/TC 211

“Geographic information/Geomatics” of the International Organization for Standardization (ISO) and has been

taken over as EN ISO 6709:2009 by Technical Committee CEN/TC 287 “Geographic Information” the

secretariat of which is held by NEN.

This European Standard shall be given the status of a national standard, either by publication of an identical

text or by endorsement, at the latest by December 2009, and conflicting national standards shall be withdrawn

at the latest by December 2009.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech

Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,

Sweden, Switzerland and the United Kingdom.
Endorsement notice

The text of ISO 6709:2008, including Cor 1:2009 has been approved by CEN as a EN ISO 6709:2009 without

any modification.
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SIST EN ISO 6709:2009
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SIST EN ISO 6709:2009
INTERNATIONAL ISO
STANDARD 6709
Second edition
2008-07-15
Standard representation of geographic
point location by coordinates
Représentation normalisée des latitude, longitude et altitude pour la
localisation des points géographiques
Reference number
ISO 6709:2008(E)
ISO 2008
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
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COPYRIGHT PROTECTED DOCUMENT
© ISO 2008

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,

electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or

ISO's member body in the country of the requester.
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Published in Switzerland
ii © ISO 2008 – All rights reserved
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
Contents Page

Foreword............................................................................................................................................................ iv

Introduction ........................................................................................................................................................ v

1 Scope ..................................................................................................................................................... 1

2 Conformance......................................................................................................................................... 1

3 Normative references ........................................................................................................................... 1

4 Terms and definitions........................................................................................................................... 2

5 Abbreviated terms ................................................................................................................................ 3

6 Requirements for the representation of geographic point location................................................ 3

6.1 Conceptual model for geographic point locations............................................................................ 3

6.2 Elements required for geographic point location ............................................................................. 5

6.3 Coordinate Reference System identification ..................................................................................... 5

6.4 Representation of horizontal position................................................................................................ 5

6.5 Representation of vertical position..................................................................................................... 6

6.6 Coordinate resolution........................................................................................................................... 6

6.7 Utilization of geographic point locations ........................................................................................... 6

7 Representation of geographic point location .................................................................................... 6

7.1 UML model............................................................................................................................................. 6

7.2 XML representation .............................................................................................................................. 6

7.3 Text string representation ................................................................................................................... 7

Annex A (normative) Conformance and abstract test suite .......................................................................... 8

Annex B (informative) Latitude and longitude coordinates are not unique ............................................... 10

Annex C (normative) UML description for representation of geographic point locations ....................... 12

Annex D (informative) Representation of latitude and longitude at the human interface ........................ 17

Annex E (informative) Latitude and longitude resolution ............................................................................ 19

Annex F (informative) Utilization of Geographic Point Locations............................................................... 20

Annex G (informative) Examples of XML representation............................................................................. 23

Annex H (informative) Text string representation of point location............................................................ 25

Bibliography ..................................................................................................................................................... 28

© ISO 2008 – All rights reserved iii
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies

(ISO member bodies). The work of preparing International Standards is normally carried out through ISO

technical committees. Each member body interested in a subject for which a technical committee has been

established has the right to be represented on that committee. International organizations, governmental and

non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the

International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. Draft International Standards

adopted by the technical committees are circulated to the member bodies for voting. Publication as an

International Standard requires approval by at least 75 % of the member bodies casting a vote.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. ISO shall not be held responsible for identifying any or all such patent rights.

ISO 6709 was prepared by Technical Committee ISO/TC 211, Geographic information/Geomatics.

This second edition cancels and replaces the first edition (ISO 6709:1983), which has been technically revised.

The first edition provided for the representation of latitude and longitude for geographic point locations. This

second edition extends the use of the representation to applications requiring latitude or longitude values to be

quoted separately, for example when quoting a difference in two meridian values. It also extends the

representation of latitude and longitude to allow the values for each to be held in separate numeric fields.

This second edition additionally provides for the representation of horizontal point location by coordinates

other than latitude and longitude, and makes provisions for a variable-length format which has the flexibility to

cover these various requirements. It also includes provisions for heights and depths.

This second edition is primarily intended for data interchange between computer systems. Informative

Annex D, which summarises the different requirements at the human interface, has been added.

The first edition used the term altitude to describe vertical position. This International Standard uses the more

general term height and also allows for vertical location to be described as depth.

iv © ISO 2008 – All rights reserved
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
Introduction

Efficient interchange of geographic-point-location data requires formats which are universally interpretable and

which allow identification of points on, above and below the earth’s surface. Users in various disciplines may

have different requirements. This is exemplified by the use of degrees and decimal degrees, as well as the

traditional degrees, minutes and seconds, for recording latitude and longitude. Users may also require various

levels of precision and may use latitude and longitude without height.
The use of this International Standard will
a) reduce the cost of interchange of data,

b) reduce the delay in converting non-standard coding structures in preparation for interchange by providing

advance knowledge of the standard interchange format, and
c) provide flexible support for geographic point representation.
© ISO 2008 – All rights reserved v
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SIST EN ISO 6709:2009
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SIST EN ISO 6709:2009
INTERNATIONAL STANDARD ISO 6709:2008(E)
Standard representation of geographic point location by
coordinates
1 Scope

This International Standard is applicable to the interchange of coordinates describing geographic point

location. It specifies the representation of coordinates, including latitude and longitude, to be used in data

interchange. It additionally specifies representation of horizontal point location using coordinate types other

than latitude and longitude. It also specifies the representation of height and depth that may be associated

with horizontal coordinates. Representation includes units of measure and coordinate order.

This International Standard is not applicable to the representation of information held within computer

memories during processing and in their use in registers of geodetic codes and parameters.

This International Standard supports point location representation through the eXtensible Markup Language

(XML) and, recognizing the need for compatibility with the previous version of this International Standard,

ISO 6709:1983, allows for the use of a single alpha-numeric string to describe point locations.

For computer data interchange of latitude and longitude, this International Standard generally suggests that

decimal degrees be used. It allows the use of sexagesimal notations: degrees, minutes and decimal minutes

or degrees, minutes, seconds and decimal seconds.

This International Standard does not require special internal procedures, file-organization techniques, storage

medium, languages, etc., to be used in its implementation.
2 Conformance

To conform to this International Standard, representations of point locations by coordinates shall satisfy all of

the conditions specified in the abstract test suite (see Annex A).
3 Normative references

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

document (including any amendments) applies.

ISO/IEC 8859-1, Information technology — 8-bit single-byte coded graphic character sets — Part 1: Latin

alphabet No. 1
ISO/TS 19103, Geographic information — Conceptual schema language
ISO 19107, Geographic Information — Spatial schema
ISO 19111:2007, Geographic Information — Spatial referencing by coordinates
ISO 19115:2003, Geographic Information — Metadata
ISO 19118, Geographic information — Encoding
© ISO 2008 – All rights reserved 1
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
ISO/TS 19127, Geographic Information — Geodetic codes and parameters

ISO 19133, Geographic Information — Location based services — Tracking and navigation

4 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1
accuracy

closeness of agreement between a test result or measurement result and the true value

[ISO 3534-2:2006]
4.2
altitude
height where the chosen reference surface is mean sea level
4.3
coordinate

one of a sequence of n numbers designating the position of a point in n-dimensional space

NOTE In a coordinate reference system, the coordinate numbers are qualified by units.

[ISO 19111:2007]
4.4
coordinate set
collection of coordinate tuples related to the same coordinate reference system
[ISO 19111:2007]
4.5
coordinate tuple
tuple composed of a sequence of coordinates

NOTE The number of coordinates in the coordinate tuple equals the dimension of the coordinate system; the order of

coordinates in the coordinate tuple is identical to the order of the axes of the coordinate system.

[ISO 19111:2007]
4.6
depth

distance of a point from a chosen reference surface measured downward along a line perpendicular to that

surface
NOTE A depth above the reference surface will have a negative value.
[ISO 19111:2007]
4.7
height
h, H

distance of a point from a chosen reference surface measured upward along a line perpendicular to that

surface
NOTE A height below the reference surface will have a negative value.
[ISO 19111:2007]
2 © ISO 2008 – All rights reserved
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
4.8
metadata
data about data
[ISO 19115:2003]
4.9
precision
measure of the repeatability of a set of measurements
[ISO 19116:2004]
4.10
resolution
〈coordinate〉 unit associated with the least significant digit of a coordinate

NOTE Coordinate resolution may have linear or angular units depending on the characteristics of the coordinate

system.
4.11
sexagesimal degree
angle represented by a sequence of values in degrees, minutes and seconds

NOTE In the case of latitude or longitude, it may also include a character indicating hemisphere.

EXAMPLE 50,079 572 5 degrees is represented as 50º04'46,461" sexagesimal degrees.

4.12
tuple
ordered list of values
[ISO 19136:2007]
5 Abbreviated terms
CRS Coordinate Reference System
GPL Geographic Point Location
GML Geography Markup Language
UML Unified Modelling Language
XML eXtensible Mark-up Language
6 Requirements for the representation of geographic point location
6.1 Conceptual model for geographic point locations

A coordinate is one of a sequence of numbers describing the position of a point. A coordinate tuple is

composed of a sequence of coordinates describing one position.

EXAMPLE A coordinate tuple consisting of latitude, longitude and height represents a 3-dimensional geographic

position.
© ISO 2008 – All rights reserved 3
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SIST EN ISO 6709:2009
ISO 6709:2008(E)

A coordinate tuple represents a location unambiguously only if the coordinate reference system (CRS) to

which it is referenced is identified. Without this identification, uncertainty in position may result in the location

being as much as several hundred metres distant, see Annex B. ISO 19111 defines the elements required to

describe a coordinate reference system.

A coordinate set is a collection of coordinate tuples. ISO 19111 requires that all coordinate tuples within a

coordinate set should be referenced to the same coordinate reference system. If only one point is being

described, the association between the coordinate tuple and coordinate reference system may be direct. For a

coordinate set, one CRS identification or definition is associated with the coordinate set and all coordinate

tuples in that coordinate inherit that association. The conceptual relationship between the coordinate tuple,

coordinate set and coordinate reference system is illustrated in Figure 1 and is formally described in UML in

Annex C.

Figure 1 — Conceptual relationship of coordinates to a Coordinate Reference System (CRS)

Coordinates within a 2-dimensional CRS describe horizontal location. Given the importance of integrating the

vertical dimension in modern systems, this International Standard also allows for the representation of

coordinates describing a 3-dimensional position. A description of geographical point location in 3 dimensions

can be made with reference to either a 3-dimensional CRS or a compound CRS consisting of a horizontal

CRS and a vertical CRS. A coordinate reference system is comprised of one coordinate system and one

datum as presented in Figure 2.
Figure 2 — Conceptual model of a Coordinate Reference System
4 © ISO 2008 – All rights reserved
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
6.2 Elements required for geographic point location

In this International Standard, geographic point location shall be represented by four elements:

⎯ coordinate representing “x” horizontal position such as latitude;
⎯ coordinate representing “y” horizontal position such as longitude;

⎯ for 3-dimensional point locations, a value representing vertical position through either height or depth;

⎯ a coordinate reference system identification.
6.3 Coordinate Reference System identification

A CRS identification shall be given for geographic point locations to be described unambiguously. For point

location including the vertical position, a compound CRS identification shall be given; this compound CRS

identification shall cover both horizontal and vertical positions. It is recognized that, in the absence of the CRS

identification, a level of uncertainty in geographic point location is introduced. This geographic offset in

position may be as much as 1 km from an actual point location as presented in Annex B.

A CRS description shall be through either

a) a reference to a definition in a register of geodetic codes and parameters conforming to the requirements

of ISO/TS 19127, or
b) a full CRS definition, as defined in ISO 19111.

Methods a) and b) are alternative means of providing a full CRS definition. Method a) is recommended for

simplicity but if the system definition is not available from a register it shall be given in full. In both methods,

the CRS defines the order of coordinates in each coordinate tuple, units and representation of the values.

For some interchange purposes, it is sufficient to confirm the identity of the system without necessarily having

the full system definition. When using method a), reference to a geodetic register, applications that only

require to confirm the identification of a CRS can do so through the register citation and CRS unique

identifier from that register. They do not need to retrieve the elements that constitute the CRS definition from

the register, unless there is a need to quote these or to perform a coordinate operation on the coordinate set.

The syntax required for the CRS definition by geodetic register in method a) above shall be as follows:

1) for an online register:
crsName=”url”
EXAMPLE crsName=”http://www.xxxx.org#xxxx:1234”; or
2) for a register which is not online:
crsName=[registerID]:[register’s CRS ID].
EXAMPLE crsName=xxxx:1234.
6.4 Representation of horizontal position

Horizontal position shall be described through a pair of coordinates. Any coordinate reference system type as

described in ISO 19111 may be used. The positive directions of each coordinate axis, the order of the

coordinates and their units shall be as described in the coordinate reference system definition, when provided.

When no CRS is provided, the following shall apply.
© ISO 2008 – All rights reserved 5
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SIST EN ISO 6709:2009
ISO 6709:2008(E)

a) Within a coordinate tuple, the latitude value shall precede the longitude value.

b) Latitudes on or north of the equator shall be positive. Latitudes south of the equator shall be negative.

c) Longitudes on or east of the prime meridian shall be positive, longitudes west of the prime meridian shall

be negative. The 180th meridian shall be negative. The prime meridian shall be Greenwich.

d) For digital data interchange, decimal degrees shall be the preferred representation. However, for

backward compatibility with the first edition of this International Standard, sexagesimal degrees may be

used. Recommendations for display of latitude and longitude at the human interface are given in Annex D.

6.5 Representation of vertical position

Vertical position shall be height or depth as described by the coordinate reference system definition. Heights

measured upward from the origin shall be positive. Heights measured downward from the origin shall be

negative. Depths measured downward from the origin shall be positive. Depths measured upward from the

origin shall be negative.
If height or depth is given:

a) whether the value is a height or a depth, shall be defined in the CRS definition;

b) the position of the value in the coordinate tuple shall be given in the CRS definition;

c) the unit for the height or depth value shall be given in the CRS definition;
d) the origin for height or depth shall be defined in the CRS definition.
6.6 Coordinate resolution

Coordinates shall be given to a resolution commensurate with the position accuracy. Accuracy may be

described through metadata as defined in ISO 19115. The linear equivalent for angular coordinates (latitude

and longitude) is given in Annex E.
6.7 Utilization of geographic point locations

ISO 19115 gives details of ISO requirements for describing metadata for geospatial information. Examples of

geographic point locations where coordinates and other attributes, such as date stamps or descriptive

information associated with the geographic point location(s), are described in Annex F.

7 Representation of geographic point location
7.1 UML model

The UML model for the representation of geographic point location is described in Annex C.

7.2 XML representation

This International Standard supports GML, an XML grammar written in XML schema for the description of

application schemas, as well as for the transport and storage of geographic information, but it also supports

flexibility regarding geographic-point-location representations that will be addressed through a register.

Examples of geographic point location through GML are given in Annex G.
6 © ISO 2008 – All rights reserved
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
7.3 Text string representation

The representation of geographic point location by latitude, longitude and, optionally, height or depth through

the text string defined in the first edition of this International Standard has, in this edition, been extended to

include CRS identification. This optional text string representation to exchange geographic-point-location

information, if used, shall be required to conform to the representation described in Annex H.

© ISO 2008 – All rights reserved 7
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SIST EN ISO 6709:2009
ISO 6709:2008(E)
Annex A
(normative)
Conformance and abstract test suite
A.1 Conformance with this International Standard
A.1.1 Conformance requirement

Conformance requirement: Any geographic point location, expressed by coordinates, shall pass all the

requirements described in the following abstract test suite.
A.1.2 Abstract test suite for conformance
A.1.2.1 Test Case Identifier: elements required for a geographic point location

a) Test purpose: Verify that all elements required for a geographic point location are complete.

b) Test method: Check the elements described and confirm that all required elements are present.

c) Reference: 6.2.
d) Test type: basic.
A.1.2.2 Test Case Identifier: Description of a CRS from a register
a) Test purpose: Verify that the description is complete and unambiguous.

b) Test method: Check the description given and confirm that it contains a sufficient definition of the CRS

and that it is applicable to the point location.
c) Reference: 6.3 and ISO/TS 19127.
d) Test type: basic.
A.1.2.3 Test Case Identifier: definition of CRS

a) Test purpose: Verify that the full CRS definition conforms to the requirements of ISO 19111.

b) Test method: Check the definition given against the information required by I
...

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