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ppl/interfaces/Prolog Prolog_interface.dox
by Patricia Hill 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: hill(a)cs.unipr.it 2002-06-10 13:45:58 Modified files: interfaces/Prolog: Prolog_interface.dox Log message: Added grammar for intervals and description for ppl_Polyhedron_get_bounding_box/2 Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/interfaces/Prolog/Prolog_inte…

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[Fwd: Re: Bug affecting mpq_class::get_num() and mpq_class::get_den()?]
by Roberto Bagnara 10 Jun '02

10 Jun '02

Dear Gerardo, I am forwarding this to the mailing list as I am sure others are interested in this issue. If I understand correctly, in GMP 4.0.1 and 4.1 there is no way to obtain an mpz_class& (or const mpz_class&) to the numerator or denominator of an mpq_class, right? In other words, is it correct to say that numerator and denominator as mpz_class objects can only be obtained by making copies? All the best Roberto -------- Original Message -------- Subject: Re: Bug affecting mpq_class::get_num() and mpq_class::get_den()? Date: Mon, 10 Jun 2002 12:20:24 +0200 From: gerardo.ballabio(a)unimib.it (Ballabio Gerardo - Dip. di Scienza dei Materiali) To: Kevin Ryde <user42(a)zip.com.au> CC: Roberto Bagnara <bagnara(a)cs.unipr.it>, Torbjorn Granlund <tege(a)swox.se> References: <87k7p9bdqi.fsf(a)zip.com.au> On 2002.06.09 00:35 Kevin Ryde wrote: > This bug report looks real unfortunately. Is it perhaps due to the > difference between "mpz_classref" and "mpz_class&"? > mpz_class::get_num seems to work in other simpler contexts. > $ g++ -W -Wall -c gmpbug.cc > gmpbug.cc: In function `mpz_class& numerator(mpq_class&)': > gmpbug.cc:24: could not convert `__gmp_expr<__gmpq_value, > __gmpq_value>::get_num()' to `mpz_class&' > > #include <gmpxx.h> > > mpz_class& > numerator(mpq_class& r) { > return r.get_num(); > } Yes, you got the point. "mpz_classref" is not the same as "mpz_class &", and I can't define a conversion from "mpz_classref" to "mpz_class &" because there's _no_ "mpz_class" to be referenced! Indeed, such an "mpz_class" could only be a temporary object, and it wouldn't be correct to take a reference to it -- as soon as the temporary goes out of scope (in your example, as soon as numerator() is exited and the reference is returned!), the reference is broken. (Furthermore, in the current implementation, creating an mpz_class from an mpz_t makes a _copy_ of the original mpz_t, thus we could read but not write to it!) As far as I can see, the only way out is to add two mpz_classes to the representation of mpq_class, and "symlink" the two underlying mpz_t's to the mpq_t (or remove the mpq_t and rewrite all mpq operations in terms of mpz operations, but I don't think we want to): then we can throw away mpz_classref, and reference the two mpz_classes directly. That would also be a considerable simplification of the implementation; but I don't know very much about the internals of mpz_t and mpq_t, and I'm not sure that such "symlinking" can be done (actually, I looked into gmp.h, but I'm quite confused about mpz_t being defined as "typedef __mpz_struct mpz_t[1];"). Otherwise, I can only suggest to leave the code as it is, and to change the documentation like this: mpz_classref mpq_class::get_num () mpz_classref mpq_class::get_den () Get an `mpz_classref' referencing to the numerator or denominator of an `mpq_class'. This can be used both for read and write access. If the object returned is modified, it modifies the original `mpq_class'. `mpz_classref' is an internal GMP++ type acting like an `mpz_class &'. You can use it as if it were an `mpz_class', except that you can't take a reference to that (nonexisting) `mpz_class' -- this includes passing it to a function that requires an `mpz_class &' argument. Do you feel this is too big a limitation? Gerardo -- Prof. Roberto Bagnara Computer Science Group Department of Mathematics, University of Parma, Italy http://www.cs.unipr.it/~bagnara/ mailto:bagnara@cs.unipr.it

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ppl/tests boundingbox1.cc
by Patricia Hill 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: hill(a)cs.unipr.it 2002-06-10 11:45:00 Modified files: tests : boundingbox1.cc Log message: Now it exits with return value 1 if the boxes are not as expected. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/tests/boundingbox1.cc.diff?cv…

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ppl interfaces/Prolog/ppl_prolog.icc src/Bound ...
by Roberto Bagnara 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: roberto(a)cs.unipr.it 2002-06-10 11:07:59 Modified files: interfaces/Prolog: ppl_prolog.icc src : BoundingBox.hh ConSys.defs.hh Constraint.defs.hh GenSys.defs.hh Log message: ppl_new_Polyhedron_from_bounding_box/3 sketched. Class Parma_Polyhedra_Library::BoundingBox fixed. Inserted several temporary kludges related to the interaction of templates, access control, and the way we produce ppl_install.hh. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/interfaces/Prolog/ppl_prolog.… http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/BoundingBox.hh.diff?cvsro… http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/ConSys.defs.hh.diff?cvsro… http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/Constraint.defs.hh.diff?c… http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/GenSys.defs.hh.diff?cvsro…

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ppl/interfaces/Prolog clpq2.pl
by Patricia Hill 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: hill(a)cs.unipr.it 2002-06-10 10:31:02 Modified files: interfaces/Prolog: clpq2.pl Log message: clpq2.pl now can handle strict constraints. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/interfaces/Prolog/clpq2.pl.di…

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ppl/src BoundingBox.hh
by Roberto Bagnara 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: roberto(a)cs.unipr.it 2002-06-10 10:13:19 Modified files: src : BoundingBox.hh Log message: Complete this implementation of bounding boxes. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/BoundingBox.hh.diff?cvsro…

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ppl/src Polyhedron.defs.hh
by Roberto Bagnara 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: roberto(a)cs.unipr.it 2002-06-10 10:03:22 Modified files: src : Polyhedron.defs.hh Log message: Fix the comment fix. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/Polyhedron.defs.hh.diff?c…

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ppl/src Polyhedron.defs.hh
by Roberto Bagnara 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: roberto(a)cs.unipr.it 2002-06-10 10:02:23 Modified files: src : Polyhedron.defs.hh Log message: Comment fixed. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/Polyhedron.defs.hh.diff?c…

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ppl/tests boundingbox1.cc
by Roberto Bagnara 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: roberto(a)cs.unipr.it 2002-06-10 09:56:58 Modified files: tests : boundingbox1.cc Log message: Added operator==() and operator!=() for BInterval and BBox. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/tests/boundingbox1.cc.diff?cv…

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ppl/interfaces/Prolog ppl_prolog.icc
by Roberto Bagnara 10 Jun '02

10 Jun '02

CVSROOT: /cvs/ppl Module name: ppl Changes by: roberto(a)cs.unipr.it 2002-06-10 09:40:26 Modified files: interfaces/Prolog: ppl_prolog.icc Log message: Formatting changes. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/interfaces/Prolog/ppl_prolog.…

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