CoCoA

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