#11854: Fix conversion QQ -> PARI
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Reporter: jdemeyer | Owner: was
Type: defect | Status: needs_review
Priority: major | Milestone: sage-4.7.3
Component: interfaces | Keywords:
Work_issues: | Upstream: N/A
Reviewer: | Author: Jeroen Demeyer
Merged: | Dependencies: #11611, #11685
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Changes (by jdemeyer):
* dependencies: #11685 => #11611, #11685
Old description:
> Same problem as #11611 but for `QQ` instead of `ZZ`::
> {{{
> sage: foo = pari(2^(32*1024));
> sage: hash(pari(QQ(1)))
> -8646911284551352313
> sage: foo = pari(0xDEADBEEF * (2^(32*1024)-1)//(2^32 - 1));
> sage: hash(pari(QQ(1)))
> -5476377146882523129
> }}}
New description:
Same problem as #11611 but for `QQ` instead of `ZZ`, the hash of an
element depends on previous garbage on the PARI stack. This is because
the conversion QQ->PARI is not done properly.
{{{
sage: foo = pari(2^(32*1024));
sage: hash(pari(QQ(1)))
-8646911284551352313
sage: foo = pari(0xDEADBEEF * (2^(32*1024)-1)//(2^32 - 1));
sage: hash(pari(QQ(1)))
-5476377146882523129
}}}
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Ticket URL: <http://trac.sagemath.org/sage_trac/ticket/11854#comment:6>
Sage <http://www.sagemath.org>
Sage: Creating a Viable Open Source Alternative to Magma, Maple, Mathematica,
and MATLAB
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