Re: P1788 Clauses 1 and 2
<<Discard previous effort. I put one of the ** in the wrong place. I think this is correct>>
P1788
On 1 Dec 2012, at 22:51, Michel Hack wrote:
> This is an excellent piece of work, and a pleasure to read...
Thank you on behalf of me & all who contributed.
>
> I jumped however upon reading the very first sentence:
>
> This standard specifies ... following ... at least one floating-point
> type defined by the IEEE-754/2008 standard.
>
> When did we decide this? We were going to have additional requirements
> for joint compliance with 1788 and 754 *if* a 754-type was supported,
> but I thought it was going to be possible to be 1788-compliant without
> using 754-types.
>
> I realise that the "Scope" is (I think) not really normative, but this
> should (if *unintended*) probably be rephrased, e.g.
>
> ...and at least one fully-specified numeric type
> such as an IEEE-754/2008 floating-point type.
This made me search my files and I saw that what I included (with changes of tense) is not exactly the text in the approved PAR, but a slightly earlier draft. The piece of text under discussion has been changed in the final PAR. See below. Michel, would that text, delimited by **, remove your objection? (I wonder if you suggested that change, back in 2008?)
John Pryce
"Scope" in actual PAR, approval date 12 Jun 2008:
> **This standard specifies basic interval arithmetic (IA) operations selecting and following one of the commonly used mathematical interval models. This standard supports the IEEE-754/2008 floating point types of practical use in interval computations.** Exception conditions will be defined and standard handling of these conditions will be specified. Consistency with the model is tempered with practical considerations based on input from representatives of vendors and owners of existing systems.
> The standard provides a layer between the hardware and the programming language levels. It does not mandate that any operations be implemented in hardware. It does not define any realization of the basic operations as functions in a programming language.
"Scope" in what seems the last draft exchanged between RBK & JDP, sent by him 7 Apr 2008:
> This standard will specify basic interval arithmetic (IA) operations selecting and following one of the commonly used mathematical interval models and at least one floating-point type defined by the IEEE-754/2008 standard. Exception conditions will be defined and standard handling of these conditions will be specified. Consistency with the model will be tempered with practical considerations based on input from representatives of vendors and owners of existing systems.
> The standard will provide a layer between the hardware and the programming language levels. It will not mandate that any operations be implemented in hardware. It will not define any realization of the basic operations as functions in a programming language.
"Scope" as in current text that is the subject of Motion 39:
> This standard specifies basic interval arithmetic (IA) operations selecting and following one of the commonly used mathematical interval models and at least one floating-point type defined by the IEEE-754/2008 standard. Exception conditions are defined and standard handling of these conditions are specified. Consistency with the model is tempered with practical considerations based on input from representatives of vendors and owners of existing systems.
> The standard provides a layer between the hardware and the programming language levels. It does not mandate that any operations be implemented in hardware. It does not define any realization of the basic operations as functions in a programming language.