Activity

John Abbott's activity

From 16 Nov 2021 to 15 Dec 2021

00:11 CoCoA-5 Bug #1640: MinSubsetOfGens does not find min subset: I have now re-read the manual, and understood what it was trying to say.
Maybe re-write the manual entry to make it ... John Abbott
00:09 CoCoA-5 Bug #1640: MinSubsetOfGens does not find min subset: I had wanted to show @MinSubsetOfGens@ to my students, but maybe it is better not to do so.
The code is weird; I a... John Abbott
00:08 CoCoA-5 Bug #1640 (Closed): MinSubsetOfGens does not find min subset: Not sure what @MinSubsetOfGens@ does, but it does not find a min card subset of the gens which generate the same idea... John Abbott
20:26 CoCoA-5 Bug #1639: RealRoots: crashes after interrupting: I still get a crash with @product([x-k | k in 0..600])@ and interrupting after about 20s.
Trying with 500 instead of... John Abbott
17:49 CoCoA-5 Bug #1639 (New): RealRoots: crashes after interrupting: Naturally I discovered this while giving a demo to my students...... John Abbott

20:37 CoCoA-5 Slug #1638: MinSubsetOfGens sometimes very slow: There are only 256 subsets to try; and some can be quickly eliminated.
I saw the source, and understand that it is n... John Abbott
20:35 CoCoA-5 Slug #1638 (New): MinSubsetOfGens sometimes very slow: I have just tried @MinSubsetOfGens@, and was surprised how slow it was on a small example.... John Abbott

14:49 CoCoALib Feature #1637 (New): Intersection of Ideals: has GBasis?: When one computes the intersection of two ideals, are the resulting generators a GBasis?
Sometimes they are: can we ... John Abbott

18:48 CoCoA-5 Bug #1104: Eigenvectors: inconsistent return type: Here is an observation about the given example:
* in the case that the eigenvalue is rational (_i.e._ in the field),... John Abbott
18:44 CoCoA-5 Slug #1629: RingElem slow with many indets: Anna implemented a quick fix: it was much faster, but would also sometimes give a wrong answer (we understood why).
... John Abbott
15:03 CoCoA-5 Slug #1629 (In Progress): RingElem slow with many indets: Simpler test:... John Abbott
17:10 CoCoALib Support #262: Play with GIT: Does anyone have useful experience to help decide between Github/Gitlab/other? And also how one goes about in practice? John Abbott
17:08 CoCoALib Support #262: Play with GIT: Florian and Bernhard suggest putting the source on Github/Gitlab.
John Abbott

17:13 CoCoA-5 Support #1636 (In Progress): Missing/Incomplete manual entries: Some entries in the online manual are missing or very incomplete.... John Abbott
16:47 CoCoALib Feature #1635 (In Progress): NR for polys with coeffs in PID: Make @NR@ work also polys with coeffs in a PID (at least in @ZZ@).
This is a stepping stone to GBasis over @ZZ@. John Abbott

22:06 CoCoALib Support #256 (Resolved): Improve doc about ordering/grading for poly rings: I think the doc in @SparsePolyRing.txt@ is OK now. Do you agree, Anna?
John Abbott

20:29 CoCoA-5 Bug #1634: Unexpected or unhelpful error using GroebnerFanIdeals: Here is a simpler failing example: I have just reduced the exponents... John Abbott
20:23 CoCoA-5 Bug #1634: Unexpected or unhelpful error using GroebnerFanIdeals: I find the error quite surprising; at least the particular error that was thrown.
I had half expected there to be so... John Abbott
20:21 CoCoA-5 Bug #1634 (In Progress): Unexpected or unhelpful error using GroebnerFanIdeals: Here is the troublesome input: it throws *@ArgTooBig@*... John Abbott
20:19 CoCoA-5 Design #984: GroebnerFanIdeals: order matrices sometimes have "large" entries: It seems that the first two rows are "almost parallel" -- why should that be?
Anyway, it should be easy to reduce th... John Abbott

17:05 CoCoALib Feature #743: Better errors: give supplementary info about the error: Anna suggests that the error message should also indicate which args (via their indices, starting from 0 or 1?)
For ... John Abbott

12:04 CoCoALib Feature #1633: Make polynomial multiplication interruptible?: This is weird. I reverted to the old code because I wanted to confirm that it is not interruptible.
Indeed, it took... John Abbott
11:59 CoCoALib Feature #1633: Make polynomial multiplication interruptible?: I have just inserted a @CheckForInterrupt@ in the main loop for multiplication.
The simpler test example from commen... John Abbott
11:53 CoCoALib Feature #1633 (In Progress): Make polynomial multiplication interruptible?: Here is a simpler test example... John Abbott
11:50 CoCoALib Feature #1633: Make polynomial multiplication interruptible?: The relevant source code is probably @myMul@ in @SparsePolyOps-RingElem.C@ around line 413.
John Abbott

20:33 CoCoALib Feature #1633: Make polynomial multiplication interruptible?: One crucial factor is how much overhead it would cost if we put a check inside some inner loop.
Also how many diff... John Abbott
20:32 CoCoALib Feature #1633 (Closed): Make polynomial multiplication interruptible?: I tried a (daft) example during an exercise class today: when tried to square a large polynomial it was not possible ... John Abbott

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