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* Update headers.Gravatar Maxime Dénès2015-01-12
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* Updating headers.Gravatar herbelin2012-08-08
| | | | git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@15715 85f007b7-540e-0410-9357-904b9bb8a0f7
* Numbers and bitwise functions.Gravatar letouzey2010-12-06
| | | | | | | | | | | | | | | | | | | | | | | See NatInt/NZBits.v for the common axiomatization of bitwise functions over naturals / integers. Some specs aren't pretty, but easier to prove, see alternate statements in property functors {N,Z}Bits. Negative numbers are considered via the two's complement convention. We provide implementations for N (in Ndigits.v), for nat (quite dummy, just for completeness), for Z (new file Zdigits_def), for BigN (for the moment partly by converting to N, to be improved soon) and for BigZ. NOTA: For BigN.shiftl and BigN.shiftr, the two arguments are now in the reversed order (for consistency with the rest of the world): for instance BigN.shiftl 1 10 is 2^10. NOTA2: Zeven.Zdiv2 is _not_ doing (Zdiv _ 2), but rather (Zquot _ 2) on negative numbers. For the moment I've kept it intact, and have just added a Zdiv2' which is truly equivalent to (Zdiv _ 2). To reorganize someday ? git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@13689 85f007b7-540e-0410-9357-904b9bb8a0f7
* Numbers : also axiomatize constants 1 and 2.Gravatar letouzey2010-10-14
| | | | | | | | | | | | | | | | | Initially, I was using notation 1 := (S 0) and so on. But then, when implementing by NArith or ZArith, some lemmas statements were filled with Nsucc's and Zsucc's instead of 1 and 2's. Concerning BigN, things are rather complicated: zero, one, two aren't inlined during the functor application creating BigN. This is deliberate, at least for the other operations like BigN.add. And anyway, since zero, one, two are defined too early in NMake, we don't have 0%bigN in the body of BigN.zero but something complex that reduce to 0%bigN, same for one and two. Fortunately, apply or rewrite of generic lemmas seem to work, even if there's BigZ.zero on one side and 0 on the other... git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@13555 85f007b7-540e-0410-9357-904b9bb8a0f7
* Numbers: new functions pow, even, odd + many reorganisationsGravatar letouzey2010-10-14
- Simplification of functor names, e.g. ZFooProp instead of ZFooPropFunct - The axiomatisations of the different fonctions are now in {N,Z}Axioms.v apart for Z division (three separate flavours in there own files). Content of {N,Z}AxiomsSig is extended, old version is {N,Z}AxiomsMiniSig. - In NAxioms, the recursion field isn't that useful, since we axiomatize other functions and not define them (apart in the toy NDefOps.v). We leave recursion there, but in a separate NAxiomsFullSig. - On Z, the pow function is specified to behave as Zpower : a^(-1)=0 - In BigN/BigZ, (power:t->N->t) is now pow_N, while pow is t->t->t These pow could be more clever (we convert 2nd arg to N and use pow_N). Default "^" is now (pow:t->t->t). BigN/BigZ ring is adapted accordingly - In BigN, is_even is now even, its spec is changed to use Zeven_bool. We add an odd. In BigZ, we add even and odd. - In ZBinary (implem of ZAxioms by ZArith), we create an efficient Zpow to implement pow. This Zpow should replace the current linear Zpower someday. - In NPeano (implem of NAxioms by Arith), we create pow, even, odd functions, and we modify the div and mod functions for them to be linear, structural, tail-recursive. git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@13546 85f007b7-540e-0410-9357-904b9bb8a0f7