CoCoA

31 Jan 2022

22:12 CoCoALib Design #950: factor and SmoothFactor for integers --> FactorINT, FactorINT_TrialDiv, FactorINT_PollardRho

I have now implemented *@FactorINT@*, *@FactorINT_TrialDiv@* and *@FactorINT_PollardRho@*.
@SmoothFactor@ is now o... John Abbott

17:52 CoCoALib Design #1653: Discriminant: return value

The old impl is still in @coclib.cpkg5@ but renamed to @discriminant_old@. I'll delete it soon (after some more test... John Abbott

17:49 CoCoA-5 Bug #1651 (Resolved): SEGV subsets ??

I have modified the impl of @SubsetsN@ in @combinatoria.cpkg5@ so that it handles 2-subsets specially (avoiding recur... John Abbott

29 Jan 2022

17:06 CoCoALib Design #1653 (Resolved): Discriminant: return value

There are now 2 @resultant@ functions and 2 @discriminant@ functions(in each case with or without specified indet).
... John Abbott

17:03 CoCoALib Bug #1656 (Feedback): SEGV in resultant

The problem was in some unrefined code for computing subresultant sequences.
Now it is more robust.
John Abbott

15:22 CoCoALib Bug #1656 (Closed): SEGV in resultant

A quick way to SEGV:... John Abbott

28 Jan 2022

17:34 CoCoALib Support #1592: Normaliz 3.8.10

Winfried pointed that I'd made a typo (now fixed).
A new version (normaliz-3.9.2) should be appearing in the near fu... John Abbott

12:39 CoCoALib Support #1592 (Closed): Normaliz 3.8.10

All seems to be fine even with Normaliz-3.9.1.
John Abbott

17:30 CoCoALib Design #1653: Discriminant: return value

Since @resultant@ is closely related to @discriminant@ they should have compatible behaviour.
This includes presumab... John Abbott

12:56 CoCoALib Design #1653 (In Progress): Discriminant: return value

Anna agrees with what I'd like to do.
Should something similar be done for @resultant@ too? John Abbott

14:35 CoCoALib Design #1627 (Feedback): Use keyword "delete" for deleted functions

John Abbott

13:08 CoCoALib Feature #1633 (Feedback): Make polynomial multiplication interruptible?

John Abbott

12:41 CoCoALib Design #1655: Remove ability to compile CoCoALib against UNINSTALLED gmp?

I have just compiled successfully.
Need to update doc in ExternalLibs-GMP.txt
Anna will check in her machine soo... John Abbott

11:03 CoCoALib Design #1655 (In Progress): Remove ability to compile CoCoALib against UNINSTALLED gmp?

I think the only real change needed is in the script @configuration/gmp-find-hdr.sh@
Perhaps it should print out a h... John Abbott

10:45 CoCoALib Design #1655: Remove ability to compile CoCoALib against UNINSTALLED gmp?

JAA now thinks that what we do is wrong rather than "clever".
Unless AMB objects, we should make this change quickly.
John Abbott

10:43 CoCoALib Design #1655 (Closed): Remove ability to compile CoCoALib against UNINSTALLED gmp?

This proposal is to modify the configure script so that it does not accept an *uninstalled* GMP.
A use who does not ... John Abbott

10:31 CoCoALib Support #1591: Compilation of Normaliz

I have just checked, and observe that there is now Normaliz 3.9.1.
I shall try compiling.
*UPDATE* Compiled with... John Abbott

10:25 CoCoALib Feature #1654: New function IsInSymbols

Anna, could you please describe more explicitly what you are proposing?
I am not sure I understand from the issue de... John Abbott

08:51 CoCoALib Feature #1654 (New): New function IsInSymbols

We misuse *@AreDistinct@* to test whether a symbol is in a PolyRing.
The advantage is that *@AreDistinct@* sees just... Anna Maria Bigatti

10:22 CoCoALib Design #1649 (In Progress): Add file SparsePolyOps-vector.C

It seems that Anna accidentally reset the progress for this issue... maybe she had two browser tabs on the same issue... John Abbott

09:29 CoCoALib Design #1649: Add file SparsePolyOps-vector.C

Anna Maria Bigatti wrote:
> syz
even though this was the start of this topic, Syz of a vector should go in submod... Anna Maria Bigatti

08:37 CoCoALib Design #1649: Add file SparsePolyOps-vector.C

I think we should call this SparsePolyOps-VectorRingElem.C, or SparsePolyOps-RingElems.C (too subtle, I fear)
ad... Anna Maria Bigatti

08:30 CoCoALib Design #1649: Add file SparsePolyOps-vector.C

In @SparsePolyOps-RingElem@ we also have:
FindReducerIndex
ReduceActiveLM
reduce
Should these go in @SparsePo... Anna Maria Bigatti

08:23 CoCoALib Design #1649: Add file SparsePolyOps-vector.C

I think we should call this SparsePolyOps-VectorRingElem.C, or SparsePolyOps-RingElems.C (too subtle, I fear)
ad... Anna Maria Bigatti

08:00 CoCoALib Design #1647: Suppress zero from ideal generators? Detect 1 and simplify generators?

Following KISS strategy, I would avoid (possibly) costly operations: e.g. interreduction, duplicates (think of a mono... Anna Maria Bigatti

27 Jan 2022

19:25 CoCoALib Feature #1652: Add LM to cocoalib ?

Florian Walsh wrote:
> That makes sense. I was implementing DivAlg which seems to exist only in a cocoa package.
... Anna Maria Bigatti

14:19 CoCoALib Feature #1652: Add LM to cocoalib ?

We really need to come up with a way of making the CoCoALib documentation friendlier.
I am reasonably happy with how... John Abbott

14:02 CoCoALib Feature #1652: Add LM to cocoalib ?

That makes sense. I was implementing DivAlg which seems to exist only in a cocoa package.
I should probably use the ... Florian Walsh

11:55 CoCoALib Feature #1652: Add LM to cocoalib ?

The reason why we do not have @LM@ in cocoalib is that we prefer not to make it handy ;-)
Sounds like a joke, but ... Anna Maria Bigatti

18:43 CoCoALib Design #1647: Suppress zero from ideal generators? Detect 1 and simplify generators?

Since we do have some doubts about what exactly "cleaning" means, and whether we like the idea, I propose the followi... John Abbott

18:36 CoCoALib Design #1647: Suppress zero from ideal generators? Detect 1 and simplify generators?

After brief consideration, I have decided to keep in this issue discussion related to what "cleaning generators" migh... John Abbott

15:01 CoCoALib Design #1653: Discriminant: return value

@discriminant@ is actually two functions: univariate inputs, and multivariate input with specified indet.
The multiv... John Abbott

14:54 CoCoALib Design #1653 (Closed): Discriminant: return value

To which ring should the return value of @Discriminant@ belong?... John Abbott

14:52 CoCoA-5 Feature #1644: Allow user to choose whether to print finite field elems as symm residues or non-neg residue

The idea seems reasonable, but what names should we use?
* @AsINT_symm@ or @AsINT_Symm@
* @AsINT_NonNeg@ or @AsINT... John Abbott

14:27 CoCoA-5 Support #1650: Potentially confusing prompt: waiting for semicolon

How about *@[[command incomplete]]@*?
Though that does read rather like an error message... John Abbott

14:24 CoCoALib Design #950: factor and SmoothFactor for integers --> FactorINT, FactorINT_TrialDiv, FactorINT_PollardRho

I suggest making @SmoothFactor@ obsolescent, and just forward the call to @FactorINT_TrialDiv@.
I think I prefer @... John Abbott

12:29 CoCoALib Design #950: factor and SmoothFactor for integers --> FactorINT, FactorINT_TrialDiv, FactorINT_PollardRho

John Abbott wrote:
> * *@FactorINT_TrialDiv(N,pmax)@* trial division upto @pmax@
> Opinions?
maybe just *@Facto... Anna Maria Bigatti

26 Jan 2022

16:11 CoCoALib Feature #1652 (In Progress): Add LM to cocoalib ?

To compute the leading monomial of a polynomial in cocoalib I need to call ... Florian Walsh

15:28 CoCoA-5 Bug #1651: SEGV subsets ??

On my Mac I get... Anna Maria Bigatti

12:53 CoCoA-5 Bug #1651 (In Progress): SEGV subsets ??

I have just used @ulimit@ to increase my stacksize limit, and now I get "too many recursions":... John Abbott

15:17 CoCoALib Design #1647: Suppress zero from ideal generators? Detect 1 and simplify generators?

John Abbott wrote:
> We could also have two ways of creating ideals: _e.g._ @ideal(L)@ and @ideal_DoNotCleanGens(L)@... Anna Maria Bigatti

14:19 CoCoALib Design #1647: Suppress zero from ideal generators? Detect 1 and simplify generators?

I like the "separate concept" of "generator cleaning", and it would be nice to make it available as a function.
I am... John Abbott

14:11 CoCoALib Design #1647: Suppress zero from ideal generators? Detect 1 and simplify generators?

I have just spoken to Florian about this issue.
His initial reaction was that he wanted @gens(ideal(L))@ to be an id... John Abbott

12:46 CoCoALib Design #950: factor and SmoothFactor for integers --> FactorINT, FactorINT_TrialDiv, FactorINT_PollardRho

Another proposal:
* *@FactorINT(N,TimeOut)@* tries both @TrialDiv@ and @PollardRho@; maybe also does @IsProbPrime@ ... John Abbott

25 Jan 2022

16:32 CoCoA-5 Bug #1651: SEGV subsets ??

On Julian's computer (Linux, CoCoA-5.3.3b), it gave a controlled CoCoA-5 error: "too many recursive calls" (or simila... John Abbott

09:42 CoCoA-5 Bug #1651 (Closed): SEGV subsets ??

This was a surprise:... John Abbott

24 Jan 2022

20:42 CoCoA-5 Support #1650 (In Progress): Potentially confusing prompt: waiting for semicolon

The following could be confusing:... John Abbott

10:04 CoCoALib Design #1647 (In Progress): Suppress zero from ideal generators? Detect 1 and simplify generators?

Potentially related to this discussion...
We can create a zero ideal by supplying an empty list of gens; however, th... John Abbott

09:07 CoCoALib Slug #1646: radical: could be more clever

I think that, along the same line -- actually in the previous line ;-)
we should change ... Anna Maria Bigatti

21 Jan 2022

13:06 CoCoALib Design #1649 (Closed): Add file SparsePolyOps-vector.C

Add file SparsePolyOps-vector.C with functions interreduced (now in SparsePolyOps-interreduced.C) and syz(vector) (new) Anna Maria Bigatti

13:04 CoCoALib Support #1612 (In Progress): Merge the doc file RadicalMembership.txt into ideal.txt

Review code in @SparsePolyOps-RadicalMembership.C@.
Rename file to @SparsePolyOps-ideal-RadicalMembership.C@ (als... John Abbott

12:22 CoCoALib Feature #1619: Make saturate available in CoCoALib

In ideal.C we have *@intersect@* and *@colon@*.
We should add *@saturate@* in the same way.
(similarly, we should... Anna Maria Bigatti

12:14 CoCoALib Design #950: factor and SmoothFactor for integers --> FactorINT, FactorINT_TrialDiv, FactorINT_PollardRho

Drastic change: @FactorBound, FactorIter@ or @FactorINTBound, FactorINTIter@ or @FactorINT_bound, FactorINT_iter@? Anna Maria Bigatti

12:12 CoCoALib Design #950: factor and SmoothFactor for integers --> FactorINT, FactorINT_TrialDiv, FactorINT_PollardRho

Anna thinks a name closer to @SmoothFactor@ would be more appropriate because the fns both take 2 args...
No final d... John Abbott

11:19 CoCoALib Feature #1645: Implement monic0(f) for the case monic(0)?

Anna says it is OK to have these "dirty" functions because their names are strange.
She suggests that they each have... John Abbott

10:57 CoCoALib Design #1647: Suppress zero from ideal generators? Detect 1 and simplify generators?

Anna has some doubts.
So far we had the simple rule that @L = gens(ideal(L))@.
Also the fn *@SyzOfGens@* is defin... John Abbott

10:38 CoCoALib Slug #1646 (Closed): radical: could be more clever

John Abbott

10:27 CoCoA-5 Feature #1644 (In Progress): Allow user to choose whether to print finite field elems as symm residues or non-neg residue

Anna suggests these names: *@AsINT_Symm@* and *@AsINT_NonNeg@* (because @AsINT_LeastNonNeg@ is too long)
The idea i... John Abbott

10:12 CoCoA-5 Feature #1648 (New): ApproxSolve and RationalSolve take different input

ApproxSolve expects an ideal (0-dim) and RationalSolve a list of polynnomials.
Choose which one we want, and modify ... Anna Maria Bigatti

10:10 CoCoA-5 Bug #1640 (Closed): MinSubsetOfGens does not find min subset

We had effectively already taken into account the comment 5 above.
Anna has just changed the code slightly to orde... John Abbott

20 Jan 2022

20:32 CoCoA-5 Bug #1640: MinSubsetOfGens does not find min subset

Unfortunately I have lost the specific example (but I suppose a new one could easily be created).
I did notice the f... John Abbott

20:28 CoCoALib Slug #1646: radical: could be more clever

I have checked in my changes (and asked Anna to check them).
I have added tests (CoCoA-5 @exbugs@... currently @radi... John Abbott

19:31 CoCoALib Slug #1646 (Resolved): radical: could be more clever

The problem was that @myGBasisByHomog@ tried to homogenize all generators without checking whether they are zero.
... John Abbott

19:14 CoCoALib Slug #1646 (In Progress): radical: could be more clever

The source code for @radical@ is still in package @radical.ckpg5@.
If the ideal is 0-dim then the C++ function *@r... John Abbott

20:05 CoCoALib Design #950: factor and SmoothFactor for integers --> FactorINT, FactorINT_TrialDiv, FactorINT_PollardRho

Currently my prototype function is called *@factor_PollardRho@*.
It takes 2 args: @N@ to be factorized (non-zero int... John Abbott

19:58 CoCoALib Feature #1645 (In Progress): Implement monic0(f) for the case monic(0)?

Let's try to make a list of possible "0" functions, and their expected behaviour if given 0 as argument.
* @monic0(f... John Abbott

19:40 CoCoALib Design #1647: Suppress zero from ideal generators? Detect 1 and simplify generators?

This change does mean that the following could give @false@:... John Abbott

19:35 CoCoALib Design #1647 (Closed): Suppress zero from ideal generators? Detect 1 and simplify generators?

Should ideals suppress zero generators?
Currently we have:... John Abbott

19:02 CoCoA-5 Feature #1644: Allow user to choose whether to print finite field elems as symm residues or non-neg residue

I have just given a demo to my students of using CRT to reconstruct a large integer value.
The demo happened to work... John Abbott

15:56 CoCoALib Feature #1619: Make saturate available in CoCoALib

To my eye that syntax looks quite ugly.
Why can I not just write *@saturate(I,J)@*?
What does @MakeUnique@ do? And... John Abbott

11:51 CoCoALib Feature #1619: Make saturate available in CoCoALib

It seems like I need to call _MakeUnique(I)->mySaturate(J)_ to compute the saturation of I wrt. to J.
Florian Walsh

17 Jan 2022

13:48 CoCoALib Slug #1646: radical: could be more clever

Bug originally reported by Florian Walsh. Also:... John Abbott

12:07 CoCoALib Slug #1646 (Closed): radical: could be more clever

Who would have predicted the following behaviour?... John Abbott

09:44 CoCoALib Feature #1645: Implement monic0(f) for the case monic(0)?

John Abbott wrote:
> Right now I would be inclined to change the manual.
> I am not yet convinced that @monic0@ is ... Anna Maria Bigatti

08:49 CoCoALib Feature #1645: Implement monic0(f) for the case monic(0)?

Right now I would be inclined to change the manual.
I am not yet convinced that @monic0@ is a good idea. Can you co... John Abbott

08:44 CoCoALib Feature #1645 (In Progress): Implement monic0(f) for the case monic(0)?

... Anna Maria Bigatti

13 Jan 2022

13:07 CoCoA-5 Feature #1644: Allow user to choose whether to print finite field elems as symm residues or non-neg residue

The current impl in @SmallFpImpl.H@ expects there to be a boolean data mem which says how to print (@LeastNonNeg@ or... John Abbott

12:58 CoCoA-5 Feature #1644: Allow user to choose whether to print finite field elems as symm residues or non-neg residue

JAA thinks that allowing the user to choose should not cause any problems: it is just a matter of printing.
Mmm, w... John Abbott

12:57 CoCoA-5 Feature #1644 (In Progress): Allow user to choose whether to print finite field elems as symm residues or non-neg residue

A student here asked how to make CoCoA-5 print elements of a finite field as the least non-neg residue class represen... John Abbott

12 Jan 2022

13:57 CoCoALib Slug #1643: rref slower than expected (maybe) [[reduced row echelon form]]

Here is the test I made:... John Abbott

13:54 CoCoALib Slug #1643 (New): rref slower than expected (maybe) [[reduced row echelon form]]

I am preparing a demo for the students, and have written a naive impl of gaussian reduction to triangular form (in Co... John Abbott

10 Jan 2022

17:15 CoCoALib Design #950: factor and SmoothFactor for integers --> FactorINT, FactorINT_TrialDiv, FactorINT_PollardRho

I have now a prototype fn for finding *one* factor using @PollardRhoSeq@.
It takes as input @N>1@ to be factorized, ... John Abbott

07 Jan 2022

20:23 CoCoALib Bug #1641: gcd does not recognize univariate input

I have checked in my first change (so that Anna can experiment with it).
There is more to come (if/when I find time)... John Abbott

04 Jan 2022

11:18 CoCoALib Bug #1641 (In Progress): gcd does not recognize univariate input

I have modified the code to detect univariate inputs and to handle them "cleverly". The result is noticeably faster!... John Abbott