SIST EN ISO 10360-6:2004

Geometrical Product Specifications (GPS) - Acceptance and reverification tests for coordinate measuring machines (CMM) - Part 6: Estimation of errors in computing Gaussian associated features (ISO 10360-6:2001)

ni bilo slovenskehga naslova

Geometrische Produktspezifikation (GPS) - Annahmeprüfung und Bestätigungsprüfung für Koordinatenmessgeräte (KMG) - Teil 6: Abweichungsabschätzung beim Berechnen zugeordneter Geometrieelemente nach Gauß (ISO 10360-6:2001)

Dieser Teil von ISO 10360 legt ein Verfahren zum Testen von Software zur Berechnung zugeordneter Geometrieelemente aus Koordinatenmessungen fest. Die betrachteten Geometrieelemente sind die Gerade (in zwei und drei Dimensionen), die Ebene, der Kreis (in zwei und drei Dimensionen), die Kugel, der Zylinder, der Kegel und der Torus.
Jedes Geometrieelement, für das die Software gelten soll, erfordert einen oder mehrere getrennte Tests.
Der Test bezieht sich nur auf die Software und ist deshalb unabhängig vom Koordinatenmesssystem.
ANMERKUNG 1   Wenn das Testergebnis zeigt, dass die Leistungskennwerte für die Längenmaßparameter des zugeordneten Geometrieelementes signifikant groß sind, verglichen mit der vom KMG-Hersteller angegebenen Längenmessabweichung des KMG (siehe ISO 10360-2), dann ist die Software ungeeignet für die Anwendung auf diesem Messsystem. Andererseits gewähren kleine Leistungskennwerte als Ergebnis dieses Tests noch keine vollkommene Sicherheit, dass die Software uneingeschränkt geeignet ist, zugeordnete Geometrieelemente zu berechnen.
Dieser Teil von ISO 10360 befasst sich mit vollständigen Geometrieelementen und mit nicht-extremen Teilelementen; die Tests für Voll- und für Teilelemente sind jedoch getrennt und die Software kann einem der Tests oder beiden unterzogen werden.
Kegel mit sehr großen Öffnungswinkeln werden von dem Test nicht erfasst.
ANMERKUNG 2   Zugeordnete Kegel mit sehr großen Öffnungswinkeln sind in der Praxis unüblich und Software zur ihrer stabilen Berechnung steht kaum zur Verfügung.

Spécification géométrique des produits (GPS) - Essai de réception et de vérification périodique des machines a mesurer tridimensionnelles (MMT) - Partie 6: Estimation des erreurs dans le calcul des éléments associés Gaussiens (ISO 10360-6:2001)

La présente partie de l'ISO 10360 spécifie une méthode d'essai de logiciels utilisés pour le calcul des éléments associés à partir des mesures par coordonnées. Les éléments concernés sont la ligne (en deux et trois dimensions), le plan, le cercle (en deux et trois dimensions), la sphère, le cylindre, le cône et le tore.  Un ou plusieurs essais séparés sont exigés pour chaque élément que le logiciel prétend couvrir.  L'essai concerne le logiciel seul, et est par conséquent indépendant du système de mesure par coordonnées.  
NOTE 1 Si le résultat de l'essai indique que les valeurs de performance pour les paramètres de taille linéaires de l'élément associé sont significatives par rapport à l'erreur d'indication d'une MMT pour les mesures de tailles (voir l'ISO 10360-2), telle que fournie par le fabricant de la MMT, le logiciel n'est pas adapté à une application à ce système de mesure. Toutefois, des valeurs de faible performance, obtenues à l'issue de cet essai, ne donnent pas une assurance complète que le logiciel est totalement adapté au calcul des éléments associés.  La présente partie de l'ISO 10360 concerne les éléments complets et non les éléments extrêmement partiels; toutefois, l'essai pour des éléments complets et celui pour des éléments partiels sont séparés, et le logiciel peut être soumis à l'un ou à l'autre des essais, ou aux deux.  Les cônes ayant un très grand angle au sommet ne sont pas couverts par l'essai.  
NOTE 2 Les cônes associés ayant un très grand angle sont inhabituels en pratique, et les logiciels permettant d'obtenir un calcul stable ne sont pas largement diffusés.

Specifikacija geometrijskih veličin izdelka - Preskusi za sprejemljivost in ponovno overjanje koordinatnih merilnih strojev (KMS) - 6. del: Ocena napak pri računanju značilnosti Gaussove porazdelitve (ISO 10360-6:2001)

General Information

• Status: Published
• Publication Date: 30-Apr-2004
• ICS: 17.040.30 - Measuring instruments
• ICS: 17.040.40 - Geometrical Product Specification (GPS)
• Technical Committee: ISEL - Mechanical elements
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-May-2004
• Due Date: 01-May-2004
• Completion Date: 01-May-2004
• Ref Project: EN ISO 10360-6:2001 - Geometrical Product Specifications (GPS) - Acceptance and reverification tests for coordinate measuring machines (CMM) - Part 6: Estimation of errors in computing Gaussian associated features (ISO 10360-6:2001)

Relations

• Corrected By: SIST EN ISO 10360-6:2004/AC:2008 - Geometrical Product Specifications (GPS) - Acceptance and reverification tests for coordinate measuring machines (CMM) - Part 6: Estimation of errors in computing Gaussian associated features (ISO 10360-6:2001/Cor 1:2007)
• Effective Date: 28-Oct-2008

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 10360-6:2004
01-maj-2004
6SHFLILNDFLMDJHRPHWULMVNLKYHOLþLQL]GHOND3UHVNXVL]DVSUHMHPOMLYRVWLQSRQRYQR
RYHUMDQMHNRRUGLQDWQLKPHULOQLKVWURMHY.06GHO2FHQDQDSDNSULUDþXQDQMX
]QDþLOQRVWL*DXVVRYHSRUD]GHOLWYH,62
Geometrical Product Specifications (GPS) - Acceptance and reverification tests for
coordinate measuring machines (CMM) - Part 6: Estimation of errors in computing
Gaussian associated features (ISO 10360-6:2001)
Geometrische Produktspezifikation (GPS) - Annahmeprüfung und Bestätigungsprüfung
für Koordinatenmessgeräte (KMG) - Teil 6: Abweichungsabschätzung beim Berechnen
zugeordneter Geometrieelemente nach Gauß (ISO 10360-6:2001)
Spécification géométrique des produits (GPS) - Essai de réception et de vérification
périodique des machines a mesurer tridimensionnelles (MMT) - Partie 6: Estimation des
erreurs dans le calcul des éléments associés Gaussiens (ISO 10360-6:2001)
Ta slovenski standard je istoveten z: EN ISO 10360-6:2001
ICS:
17.040.30 Merila Measuring instruments
17.040.40 6SHFLILNDFLMDJHRPHWULMVNLK Geometrical Product
YHOLþLQL]GHOND*36 Specification (GPS)
SIST EN ISO 10360-6:2004 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 10360-6:2004

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SIST EN ISO 10360-6:2004
EUROPEAN STANDARD
EN ISO 10360-6
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2001
ICS 17.040.30
English version
Geometrical Product Specifications (GPS) - Acceptance and
reverification tests for coordinate measuring machines (CMM) -
Part 6: Estimation of errors in computing Gaussian associated
features (ISO 10360-6:2001)
Spécification géométrique des produits (GPS) - Essai de Geometrische Produktspezifikation (GPS) -
réception et de vérification périodique des machines à Annahmeprüfung und Bestätigungsprüfung für
mesurer tridimensionnelles (MMT) - Partie 6: Estimation Koordinatenmessgeräte (KMG) - Teil 6:
des erreurs dans le calcul des éléments associés Abweichungsabschätzung beim Berechnen zugeordneter
Gaussiens (ISO 10360-6:2001) Geometrieelemente nach Gauß (ISO 10360-6:2001)
This European Standard was approved by CEN on 12 November 2001.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2001 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 10360-6:2001 E
worldwide for CEN national Members.

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SIST EN ISO 10360-6:2004
EN ISO 10360-6:2001 (E)
CORRECTED 2002-02-06
Foreword
This document (ISO 10360-6:2001) has been prepared by Technical Committee ISO/TC 213
"Dimensional and geometrical product specifications and verification" in collaboration with
Technical Committee CEN/TC 290 "Dimensional and geometrical product specification and
verification", the secretariat of which is held by AFNOR.
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 June 2002, and conflicting national
standards shall be withdrawn at the latest by June 2002.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy,
Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United
Kingdom.
Endorsement notice
The text of the International Standard ISO 10360-6:2001 has been approved by CEN as a
European Standard without any modifications.
NOTE Normative references to International Standards are listed in annex ZA (normative).
2

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SIST EN ISO 10360-6:2004
EN ISO 10360-6:2001 (E)
Annex ZA
(normative)
Normative references to international publications
with their relevant European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions
of any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
NOTE Where an International Publication has been modified by common modifications,
indicated by (mod.), the relevant EN/HD applies.
Publication Year Title EN Year
ISO 10360-1 2000 Geometrical Product Specifications EN ISO 10360-1 2000
(GPS) - Acceptance and
reverification tests for coordinate
measuring machines (CMM) - Part
1: Vocabulary
ISO 10360-2 1994 Coordinate metrology - Part 2: EN ISO 10360-2 1995
Performance assessment of
coordinate measuring machines
ISO 14253-1 1998 Geometrical Product Specifications EN ISO 14253-1 1998
(GPS) - Inspection by measurement
of workpieces and measuring
equipment - Part 1: Decision rules
for proving conformance or non-
conformance with specifications
ISO 14660-1 1999 Geometrical Product Specifications EN ISO 14660-1 1999
(GPS) - Geometrical features - Part
1: General terms and definitions
ISO 14660-2 1999 Geometrical Product Specifications EN ISO 14660-2 1999
(GPS) - Geometrical features - Part
2: Extracted median line of a
cylinder and a cone, extracted
median surface, local size of an
extracted feature
3

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SIST EN ISO 10360-6:2004

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SIST EN ISO 10360-6:2004

INTERNATIONAL ISO
STANDARD 10360-6
First edition
2001-12-15


Geometrical Product Specifications
(GPS) — Acceptance and reverification
tests for coordinate measuring machines
(CMM) —
Part 6:
Estimation of errors in computing Gaussian
associated features
Spécification géométrique des produits (GPS) — Essai de réception et de
vérification périodique des machines à mesurer tridimensionnelles (MMT)
Partie 6: Estimation des erreurs dans le calcul des éléments associés
gaussiens




Reference number
ISO 10360-6:2001(E)
©
ISO 2001

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SIST EN ISO 10360-6:2004
ISO 10360-6:2001(E)
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©  ISO 2001
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ii © ISO 2001 – All rights reserved

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SIST EN ISO 10360-6:2004
ISO 10360-6:2001(E)
Contents Page
Foreword.iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .2
4 Basic requirements.2
5 Reference data sets and reference parameter values .3
6 Test parameter values and converted test parameter values.3
7 Units.4
8 Numerical uncertainty.4
9 Application of the test method.4
10 Compliance with specification .7
11 Test certificate.8
Annex A (normative) Procedure for generating reference data sets.10
Annex B (informative) Relation to the GPS matrix model.18
Bibliography.19


© ISO 2001 – All rights reserved iii

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SIST EN ISO 10360-6:2004
ISO 10360-6:2001(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 3.
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 part of ISO 10360 may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 10360-6 was prepared by Technical Committee ISO/TC 213, Dimensional and
geometrical product specifications and verification.
ISO 10360 consists of the following parts, under the general title Geometrical Product Specifications (GPS) —
Acceptance and reverification tests for coordinate measuring machines (CMM):
 Part 1: Vocabulary
 Part 2: CMMs used for measuring size
 Part 3: CMMs with the axis of a rotary table as the fourth axis
 Part 4: CMMs used in scanning measuring mode
 Part 5: CMMs using multiple-stylus probing systems
 Part 6: Estimation of errors in computing Gaussian associated features
Annex A forms a normative part of this part of ISO 10360. Annex B is for information only.
iv © ISO 2001 – All rights reserved

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SIST EN ISO 10360-6:2004
ISO 10360-6:2001(E)
Introduction
This part of ISO 10360 is a geometrical product specification (GPS) standard and is to be regarded as a general
GPS standard (see ISO/TR 14638). It influences link 5 of the chains of standards on size, distance, radius, angle,
form, orientation, location, run-out and datums.
For more detailed information of the relation of this part of ISO 10360 to other standards and the GPS matrix model
see annex B.
Coordinate measurement technology is widely used in industrial metrology to assess features of a workpiece. A
common requirement is to fit an associated feature to a data set consisting of coordinate measurements of a real
feature. This fitting is carried out by software.
Software for calculating an associated feature provides values of parameters of the associated feature that are
descriptive of the size, shape, location and orientation of the feature. These parameters are useful
 for the purpose of carrying out calculations involving the feature, often in conjunction with other associated
features and other information, and
 in determining the extent to which a workpiece satisfies dimensional and positional specifications.
The reliability of information about features that is determined from associated features is influenced by the quality
of the software for computing these features.
The tests defined in this part of ISO 10360 are concerned with assessing the correctness of the parameters of
computed associated features as measured by a coordinate measuring machine (CMM) or other coordinate
measuring system. Although different criteria may be used to compute associated features, for example, by
minimizing the Euclidean or Chebyshev norm of residuals, this test is applicable for software designed for
unconstrained Gaussian (least-squares) features.
In the case of reverification tests of CMMs, the software test of this part of ISO 10360 usually does not provide new
or different information in comparison with that obtained by an acceptance test, since software is supposed to be
stable over time. However, a reverification test of the software may be useful following possible corruption or
alteration of the software under test.
For software already in existence, the evaluation of the performance may not be obtained only by fulfilling the
requirements of this part of ISO 10360. However, such cases do not necessarily exclude the ability of the software
to perform correct computation of measurements.
This part of ISO 10360 is applicable to software submitted for test in respect of the values it provides for the
parameters of an associated feature. The test procedure is based on applying the software under test to reference
data sets, and comparing the results obtained with reference results.
© ISO 2001 – All rights reserved v

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SIST EN ISO 10360-6:2004

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SIST EN ISO 10360-6:2004
INTERNATIONAL STANDARD ISO 10360-6:2001(E)

Geometrical Product Specifications (GPS) — Acceptance and
reverification tests for coordinate measuring machines (CMM) —
Part 6:
Estimation of errors in computing Gaussian associated features
1 Scope
This part of ISO 10360 specifies a method for testing software used for computing associated features from
coordinate measurements. The features of concern are the line (in two and three dimensions), the plane, the circle
(in two and three dimensions), the sphere, the cylinder, the cone and the torus.
One or more separate tests are required for each feature claimed to be covered by the software.
The test is of the software alone and therefore independent of the coordinate measuring system.
NOTE 1 If the result of the test indicates that the performance values for linear size parameters of the associated feature are
significant compared with the error of indication of a CMM for size measurement (see ISO 10360-2), as provided by the CMM
manufacturer, the software is inadequate for application on that measuring system. However, small performance values,
obtained as a result of this test, do not provide complete assurance that the software is totally suitable for computing associated
features.
This part of ISO 10360 is concerned with complete features and non-extremely partial features; however, the test
for complete features and that for partial features are separate, and software may be submitted for either or both
tests.
Cones with very large apex angles are not covered by the test.
NOTE 2 Associated cones with very large angles are unusual in practice and the software for their stable computation is not
widely available.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 10360. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 10360 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
ISO 10360-1:2000, Geometrical product specifications (GPS) — Acceptance and reverification tests for coordinate
measuring machines (CMM) — Part 1: Vocabulary
ISO 10360-2:2001, Geometrical Product Specifications (GPS) — Acceptance and reverification tests for coordinate
measuring machines (CMM) — Part 2: CMMs used for measuring size
ISO 14253-1:1998, Geometrical product specifications (GPS) — Inspection by measurement of workpieces and
measuring equipment — Part 1: Decision rules for proving conformance or non-conformance with specifications
© ISO 2001 – All rights reserved 1

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SIST EN ISO 10360-6:2004
ISO 10360-6:2001(E)
ISO 14660-1:1999, Geometrical product specifications (GPS) — Geometrical features — Part 1: General terms and
definitions
ISO 14660-2:1999, Geometrical product specifications (GPS) — Geometrical features — Part 2: Extracted median
line of a cylinder and a cone, extracted median surface, local size of an extracted feature
International Vocabulary of Basic and General Terms in Metrology (VIM). BIPM, IFCC, IEC, ISO, IUPAC, IUPAP,
OIML, 2nd edition, 1993
3 Terms and definitions
For the purposes of this part of ISO 10360, the terms and definitions given in ISO 10360-1, ISO 14660-1,
ISO 14660-2 and VIM apply.
4 Basic requirements
The following basic requirements shall be met by the software supplier.
a) The software under test shall have an unambiguous and unique identification (e.g. a release number).
Improper applications of the test result to other versions of the software under test are forbidden. The testing
body is allowed to satisfy the request by an owner of (a license of) the software under test and its test
certificate to re-run the test based on the reference data sets identified by the release number reported in the
test certificate.
b) The software under test shall provide a means of
1) direct input of a reference data set and output of test parameter values to adequate numerical precision
(see clause 8), bypassing the measurement and software correction parts of the system, and
2) inputting 2D coordinates to the software under test for computing 2D associated features (line and circle in
two dimensions); if this is not available, it is tolerated to add a dummy null z coordinate to each point in the
reference data sets, thus projecting the feature onto the xy coordinate plane.
NOTE 1 The input and output procedures associated with some measuring systems may be limited in terms of the
numerical precision of the values transmitted. This limitation may disadvantage the software under test in terms of the
test results obtained.
c) The method of input to, and output from, the processor is to be agreed with the testing body.
NOTE 2 It may be convenient to use a standard computer-readable medium in a standard format (e.g. ASCII on a
3,5" disk).
d) Corresponding to each feature for which the software under test is to be tested, a statement of the
parametrization of the feature used by the software under test shall be provided.
NOTE 3 Reference parametrizations are given in Table 3.
e) Corresponding to each feature for which the software under test is to be tested and to the test type (see
Table 2), a statement of the maximum permissible errors, MPEq, of the relevant parameter classes (see 9.3)
shall be provided.
2 © ISO 2001 – All rights reserved

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SIST EN ISO 10360-6:2004
ISO 10360-6:2001(E)
5 Reference data sets and reference parameter values
5.1 General
The reference data sets and the corresponding reference parameter values used for the purposes of testing the
software under test shall be generated according to the procedure specified in annex A. The reference data sets
are designed to simulate a range of sizes, shapes, locations, orientations and sampling of features. They are also
designed to simulate typical CMM errors of measurement, including probing errors, and feature form deviations.
The reference data sets and the reference parameter values generated according to annex A shall be used only
once for verification of any software under test (see A.1).
5.2 Initial estimates of parameter values
Software under test may require that a subset of the points input to the software, usually the first ones in the set,
has a predefined sampling pattern. This subset is used to determine the initial estimates of the parameter values.
When this requirement is written in the operating instructions of the software under test, and upon request of the
software supplier, the testing body shall generate additional points consistent with the predefined sampling pattern.
These additional points form the subset added to the data as generated according to annex A to form a reference
data set. These circumstances shall be noted on the test certificate [see clause 11, e)].
NOTE 1 The software under test typically employs iterative methods of calculation for determining the values of the
parameters of the associated feature. For this purpose, identification of a subset of points may be required, from which initial
estimates of these values can be computed.
NOTE 2 A Gaussian associated cylinder can be used for purposes of illustration: the first six points in a reference data set
could be identified as a subset for initial-estimation purposes. For instance, the line joining the centres of the circles defined by
the first three points and the second three points could be used as an approximation to the axis of the associated cylinder, and
the radii of these circles could be used as approximations to the radius of the associated cylinder.
NOTE 3 Software under test which does not require initial estimates of the parameter values is more robust, being self-
contained, and does not impose an operating procedure for measuring real features.
6 Test parameter values and converted test parameter values
Since different software suppliers may use different parametrizations, for the purposes of the test, the test
parameter values produced by the software under test shall be modified, if necessary, by applying a conversion
rule to produce converted test parameter values. The converted test parameter values so derived correspond to the
same parametrization as the reference parameter values and can meaningfully be compared with them.
For this purpose, the software supplier shall provide full details of the test parametrization.
When necessary, the testing body shall implement and apply the appropriate conversion rule.
It is recommended that the software supplier provide test parameter values to adequate numerical resolution (see
clause 8), in order that uncertainty may not be unnecessarily added in producing converted test parameter values.
Software under test may fail to produce results for some reference data sets.
NOTE Failure to produce results may be due to, for example:
a) the software under test indicating that the data set cannot be processed because it is beyond its domain of
application (e.g. it contains too many data points or the data points are unsuitably distributed), or
b) lack of convergence of an iterative algorithm, or
c) a fatal error that has arisen during execution of the software (e.g. a floating-point overflow or an attempt to take
the square root of a negative number).
© ISO 2001 – All rights reserved 3

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SIST EN ISO 10360-6:2004
ISO 10360-6:2001(E)
7 Units
The units specified in Table 1 shall be used.
Table 1 — Units
Reference data sets Reference parameter values
Point coordinates millimetres —
Location parameters — millimetres
Size parameters — millimetres
Angle parameters — radians
a
Orientation parameters —
(dimensionless)
Submultiples, for example, micrometres and microradians, may be used on the test certificate for quoting differences
between the converted test parameter values and corresponding reference parameter values and their uncertainties.
a
The orientation parameters are expressed as direction cosines.
8 Numerical uncertainty
It is the responsibility of the testing body to evaluate any numerical uncertainty introduced by the finite number of
digits used to transfer information and to represent numerical values computationally. This numerical uncertainty
shall be included in the uncertainty statement reported in the test certificate (see clause 10).
NOTE 1 Information transferred includes point coordinates in reference data sets and reference parameter values (controlled
by the testing body), as well as test parameter values (submitted by the software supplier).
NOTE 2 The computational representation affects the calculation of reference parameter values from reference data sets (in
the case of reference software, see Figure 2) or reference data sets from reference parameter values (in the case of data
generators, see Figure 3), in applying conversion rules and in calculating q values [see 9.3, d)].
NOTE 3 The numerical uncertainty also depends on how well a Gaussian associated feature is defined by a reference data
set or, equivalently, the numerical condition of the fitting problem (a measure of the perturbation in the reference parameter
values relative to a small perturbation in the coordinate values in a reference data set). The condition is influenced by the type of
feature, and by the number and locations of points in the reference data set.
NOTE 4 The numerical uncertainty can be estimated by simulation if an analytical evaluation is not straightforward.
Depending on the manner in which the information is produced, the testing body may regard either the reference
data sets or the reference parameter values as exact, provided the appropriate uncertainty is determined in the
other.
9 Application of the test method
9.1 Principle
The principle underlying the method of test is that of comparing converted test parameter values with reference
parameter values (see Figure 1). The converted test parameter values are obtained by applying the software under
test to the reference data sets to obtain test parameter values, and by applying a conversion rule to these test
parameter values. Each reference data set and the corresponding reference parameter values are regarded as a
reference pair for testing purposes.
NOTE 1 The testing body will provide reference pairs using, for example, reference software or a data generator, as
illustrated in Figures 2 and 3.
4 © ISO 2001 – All rights reserved

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SIST EN ISO 10360-6:2004
ISO 10360-6:2001(E)
Different software under test may be intended, and regularly used, for different applications (e.g. for calculating
complete or partial features), or with measurement points affected by small or large
...