WG14 Document: N1056
Date: 2004-03-01


Date of presentation of proposal:




A proposal for a new work item shall be submitted to the secretariat of the ISO/IEC joint technical committee concerned with a copy to the ISO Central Secretariat.

Presentation of the proposal - to be completed by the proposer Guidelines for proposing and justifying a new work item are given in ISO Guide 26.


Extensions for the programming language C Standard Library to support Mathematical Special Functions.


To define extensions to the programming language C Standard Library, specified by the international standard ISO/IEC 9899:1999. These extensions will provide support for the mathematical special functions defined in the International Standard ISO 31-11:1992. ISBN 92-67-10185-4.

Purpose and justification

The programming language C as specified by the International Standard ISO/IEC 9899:1999 defines selected mathematical functions from categories of particular interest to the numerical computing communities: exponential and logarithmic functions, circular and hyperbolic functions, and a few special functions.

This NP proposes to establish a new project to produce a Technical Report (type 2) in which extensions to the C library are defined that allow programmers to fully exploit all the functionality of the mathematical special functions defined in the International Standard ISO 31-11:1992.

Several commercial C libraries support some of the mathematical special functions defined in the ISO31-11:1992 Standard. Generating a Technical Report for these special functions for the C Standard Library will give guidance to Library developers and application developers. The benefits would include consistent Library interface, improved portability, interoperability for applications, consistent behavior across many implementations.

The project also includes the production of the text for a Rationale document (either separate or as part of the project document).

Programme of work

If the proposed new work item is approved, which of the following document(s) is (are) expected to be developed?
____ a single International Standard more than one International Standard (expected number: ........ )
____ a multi-part International Standard consisting of .......... parts
____ an amendment or amendments to the following International Standard(s) ....................................
_X__ a technical report , type 2

Relevant documents to be considered

  • ISO/IEC 9899:1999 - Programming Language C
  • ISO/IEC JTC 1/SC22 WG14 N1051 - Draft Technical Report on Special Math Functions.
  • ISO/IEC JTC 1/SC22 WG21 N1422 - A Proposal to Add Mathematical Special Functions to the C++ Standard Library
  • ISO/IEC 11404:1996 - Language-independent datatypes.
  • ISO/IEC 10967-1:1994 - Language independent arithmetic -- Part 1: Integer and floating point arithmetic.

Cooperation and liaison

All ISO/IEC JTC 1/SC22 Working groups that have an interest in supporting many natural languages, especially ISO/IEC JTC 1/SC22 WG21 (C++).

Preparatory work offered with target date(s)

A PDTR document will be ready for registration 24 months after the approval of the project by JTC 1.


Will the service of a maintenance agency or registration authority be required? .......NO.............
- If yes, have you identified a potential candidate? ................
- If yes, indicate name .............................................................

Are there any known requirements for coding? ..........NO.........
-If yes, please specify on a separate page

Are there any known requirements for cultural and linguistic adaptability? .....NO....
- If yes, please specify on a separate page

Does the proposed standard concern known patented items? .......NO..........
- If yes, please provide full information in an annex

Comments and recommendations of the JTC 1 Secretariat - attach a separate page as an annex, if necessary

Comments with respect to the proposal in general, and recommendations thereon:
It is proposed to assign this new item to JTC 1/SC22 WG14
The proposed project editor is P. J. Plauger (pjp@dinkumware.com) of the United States, the proposed backup project editor is John Benito (jb@benito.com) of the United States. Both members of good standing of NCITS J11.

Voting on the proposal - Each P-member of the ISO/IEC joint technical committee has an obligation to vote within the time limits laid down (normally three months after the date of circulation).

Date of circulation:

Closing date for voting:

Signature of JTC 1 Secretary:
Lisa A. Rajchel






A Business Requirement


A.1 Market Requirement

Essential ___
Desirable ___
Supportive ___


A.2 Regulatory Context

Essential ___
Desirable ___
Supportive ___
Not Relevant ___


B. Related Work


B.1 Completion/Maintence of current standards

Yes ___


B.2 Commitment to other organization

Yes ___


B.3 Other Source of standards

Yes ___


C. Technical Status


C.1 Mature Technology

Yes ___


C.2 Prospective Technology

Yes ___


C.3 Models/Tools

Yes ___


D. Conformity Assessment and Interoperability


D.1 Conformity Assessment

Yes ___


D.2 Interoperability

Yes ___


E. Other Justification


Notes to Proforma

A. Business Relevance. That which identifies market place relevance in terms of what problem is being solved and or need being addressed.

A.1. Market Requirement. When submitting a NP, the proposer shall identify the nature of the Market Requirement, assessing the extent to which it is essential, desirable or merely supportive of some other project.

A.2 Technical Regulation. If a Regulatory requirement is deemed to exist - e.g. for an area of public concern e.g. Information Security, Data protection, potentially leading to regulatory/public interest action based on the use of this voluntary international standard - the proposer shall identify this here.

B. Related Work. Aspects of the relationship of this NP to other areas of standardization work shall be identified in this section.

B.1 Competition/Maintenance. If this NP is concerned with completing or maintaining existing standards, those concerned shall be identified here.

B.2 External Commitment. Groups, bodies, or for a external to JTC1 to which a commitment has been made by JTC for cooperation and or collaboration on this NP shall be identified here.

B.3 External Std/Specification. If other activities creating standards or specifications in this topic area are known to exist or be planned, and which might be available to JTC1 as PAS, they shall be identified here.

C. Technical Status. The proposer shall indicate here an assessment of the extent to which the proposed standard is supported by current technology.

C.1 Mature Technology. Indicate here the extent to which the technology is reasonably stable and ripe for standardization.

C.2 Prospective Technology. If the NP is anticipatory in nature based on expected or forecasted need, this shall be indicated here.

C.3 Models/Tools. If the NP relates to the creation of supportive reference models or tools, this shall be indicated here.

D. Any other aspects of background information justifying this NP shall be indicated here.

D. Conformity Assessment and Interoperability

D.1 Indicate here if Conformity Assessment is relevant to your project. If so, indicate how it is addressed in your project plan.

D.2 Indicate here if Interoperability is relevant to your project. If so, indicate how it is addressed in your project plan.