CoCoA Project

19 Feb 2021

17:26 CoCoA-5 Bug #1577 (Resolved): radical: lex order, ERROR: Ring is not standard graded

Anna has implemented the obvious workaround: map into a new poly ring (with degrevlex), and then unmap the result.
S... John Abbott

17:00 CoCoA-5 Bug #1396 (Resolved): Website: download page for CoCoA-4 burns CPU

Anna removed some Java script... now seems OK.
John Abbott

09:50 CoCoA-5 Feature #1112: New function: IsEmpty

The function *@IsEmpty@* is slower than explicitly testing for equality to the empty list; why should that be?
He... John Abbott

18 Feb 2021

22:18 CoCoA-5 Feature #1112 (Resolved): New function: IsEmpty

I have just added a first impl to @BuiltInFunctions.C@.
A couple of trivial tests passed.
Still need to: write te... John Abbott

22:07 CoCoA-5 Feature #250 (Feedback): CoCoALib BuildInfo vs CoCoA-5 VersionInfo

The code in @VersionInfo.C@ looks clean and simple to me.
I think this issue has been resolved some time ago.
Movin... John Abbott

22:05 CoCoA-5 Bug #1396: Website: download page for CoCoA-4 burns CPU

The problem still exists :-(
John Abbott

22:03 CoCoA-5 Design #474: Eliminate package BinRepr

It looks to me as though this could easily be converted into C++ (in CoCoALib).
Perhaps just an afternoon suffices..... John Abbott

22:00 CoCoA-5 Bug #1215 (Feedback): RationalSolve: gives "Error: must be non-zero"

Is this issue a *duplicate* of issue #724?
I think so. Anyway, I tried the example mentioned in the description, an... John Abbott

17:21 CoCoALib Design #1558: CpuTimeLimit: more frequent clock checks

I have revised the impl based on the results from yesterday's speed tests.
The current impl seems to work acceptab... John Abbott

17 Feb 2021

20:33 CoCoALib Design #1558: CpuTimeLimit: more frequent clock checks

I have done a speed test using the "quick" example from comment 4.
The speed penalty when I limited the number of it... John Abbott

19:03 CoCoA-5 Bug #946: Function "ideal" evaluates the argument twice

I have just checked in my revised code (even though it still needs to be cleaned).
We must develop a proper test s... John Abbott

18:33 CoCoA-5 Design #1540 (Resolved): Double power

I think I have solved the main problem and also the one mentioned in comment 2.
Solution is not elegant, but I do no... John Abbott

11:16 CoCoALib Design #1538 (Resolved): RingElem from string (ReadExpr)

I have just checked what the code does (or seems like it should do).
The current impl is:
* reading from @istream@ ... John Abbott

11:06 CoCoALib Design #1547 (Feedback): Require decimal mode for ostream?

I have changed most/all output fns so that they *assert* that the @ostream@ is in decimal mode.
Contrast with input ... John Abbott

10:27 CoCoALib Design #1547 (Resolved): Require decimal mode for ostream?

I have now added assertions to printing for @BigInt@, @BigRat@ (which anyway prints a @BigInt@), @PPMonoidElem@, and ... John Abbott

10:09 CoCoALib Design #1547 (In Progress): Require decimal mode for ostream?

I do not like the idea of converting a @BigInt@ or @BigRat@ to a non-decimal string via normal output operators.
[We... John Abbott

11:02 CoCoALib Design #1529 (Closed): INPUT questions

Closing after 2 months in feedback.
John Abbott

11:01 CoCoALib Design #1523 (Closed): Input fns: action when when istream is in bad state?

Closing after 2 months in feedback.
*One last change: input fns throw if @istream@ is not in decimal mode* John Abbott

10:02 CoCoALib Bug #1473: isystem not working as expected

*Anna:* can you check whether this is still a problem?
I suppose it is, but since I do not have access to your Mac, ... John Abbott

09:59 CoCoALib Design #794 (Rejected): ar gives warnings on fedora 23

This now very outdated (curr version of Fedora is 33) -- rejecting.
I do not recall getting warnings on my Ubuntu in... John Abbott

16 Feb 2021

18:46 CoCoALib Bug #1522: SEGV: avoid long linked lists of loaves in MemPools

I have just run the test from issue #1337.
With @MemPool@ the program took 473s; disabling @MemPool@ by setting the ... John Abbott

18:13 CoCoALib Slug #1337: PrimaryDecomposition: a interesting/pathological example

*STATUS 2021-02-16:* I confirm that the RGB took about 0.35s on my computer, while PD took 473s.
*OBSERVATION:* it... John Abbott

18:03 CoCoALib Design #786 (Resolved): MemPool: review min and max loaf sizes

After the design change noted in issue #1522#note-10, this issue is probably largely irrelevant now.
The current l... John Abbott

17:34 CoCoALib Feature #898: New function: cardinality of finite field?

I have now changed the default defn of @myLogCardinality@ so that it throws an exception; the finite fields overwrite... John Abbott

17:27 CoCoALib Feature #898: New function: cardinality of finite field?

Since we intend restricting its use to finite fields maybe the fn could be called *@FieldSize@*; error if arg is not ... John Abbott

17:19 CoCoALib Feature #1219: Frobby version number

I believe that maintenance of *Frobby* has now passed to the Macaulay group (Mike Stillman, _etc._)
We should contac... John Abbott

14:41 CoCoA-5 Bug #946: Function "ideal" evaluates the argument twice

I might have fixed this (for ideals)... and probably introduced some new weird bugs.... the interpreter code is not e... John Abbott

14:09 CoCoA-5 Slug #1392 (Resolved): ApproxSolve: another slow example

The example given is quite quick now (0.5s on my computer).
Marking as "resolved" (don't know by whom or when).
John Abbott

14:04 CoCoA-5 Bug #1574: ApproxSolveTF

The code seems to be a bit convoluted. It'll take time to work out what it is supposed to be doing... not today!
John Abbott

13:43 CoCoALib Bug #1575: DynamicBitset missing arg checks

My usual approach regarding errors and assertions is:
* if the fn is the main public fn for that operation (and docu... John Abbott

15 Feb 2021

22:49 CoCoA-5 Bug #1577: radical: lex order, ERROR: Ring is not standard graded

The full error mesg is:... John Abbott

22:48 CoCoA-5 Bug #1577 (Closed): radical: lex order, ERROR: Ring is not standard graded

This should not happen:... John Abbott

22:20 CoCoA-5 Bug #1567 (Feedback): Radical in non-zero char

I have check in the changes (some time ago). So moving status to _feedback_. John Abbott

12 Feb 2021

12:19 CoCoA-5 Bug #724 (Resolved): RationalSolve: wrongly complains about non zero-dim even in finite char

The example from issue #723 is way too slow to act as a test case -- do we have a more sane test case? How about the... John Abbott

12:16 CoCoA-5 Feature #723: Referring to indets with multiple indices from a polyring

The example in comment 2 is slow because it takes along time to test @IsZeroDim@ _i.e._ compute a GB.
I stopped th... John Abbott

11:54 CoCoA-5 Slug #1270 (Feedback): RationalSolve: use MinPolyQuot instead of elim

I have just tried the example from comment 5, and @RationalSolve@ is now tolerably fast (less than 2s).
John Abbott

11 Feb 2021

00:13 CoCoA-5 Support #1252: ShapeLemma: no manual entry

What is the status of this issue?
John Abbott

00:12 CoCoA-5 Bug #1573 (Resolved): ApproxSolve: very imprecise

I have now added an extra loop which checks the values of the polys at the points found.
If the values are not "heur... John Abbott

00:08 CoCoA-5 Bug #1216 (Feedback): RationalSolve: gives wrong answer

I have implemented the new field names, and updated doc, tests, manual.
New state: Feedback. John Abbott

17:56 CoCoA-5 Bug #1216: RationalSolve: gives wrong answer

> Possible names are *@AffinePts@* and *@ProjectivePts@* (or *@ProjPts@*).
I vote for *@AffinePts@* and *@Projecti... Anna Maria Bigatti

10 Feb 2021

22:11 CoCoALib Design #1576 (In Progress): cmp for machine integers

I have added 2 impls to *@utils.H@*; one adapted from "cppreference". Not sure how much I trust this template stuff.... John Abbott

21:46 CoCoALib Design #1576: cmp for machine integers

The impl of *@IsInRange@* should also be revised...
John Abbott

21:33 CoCoA-5 Bug #1216: RationalSolve: gives wrong answer

Feedback and constructive criticism are welcome!
I'd like to close this issue soon.
John Abbott

21:28 CoCoA-5 Bug #1216: RationalSolve: gives wrong answer

Now I wonder what the names of the fields in the records should be.
It may be sensible to use different names for th... John Abbott

20:50 CoCoA-5 Bug #1216: RationalSolve: gives wrong answer

Anna has approved the suggestion in comment 13 (just above) about returning a record.
Now I must impl, and revise th... John Abbott

20:36 CoCoALib Design #1511 (In Progress): Use C++14 constexpr

John Abbott

09 Feb 2021

15:22 CoCoA-5 Bug #727: Emacs UI: send-file (C-c C-f) should check if buffer and file are synchronized

I got caught out by this just a short while ago.
I have searched on internet, but there does not seem to be an eas... John Abbott

08 Feb 2021

16:13 CoCoALib Design #1576: cmp for machine integers

Also need to revise @test-MachineInt2.C@
Currently I have hacked it to work with the current "implementazione zoppic... John Abbott

16:12 CoCoALib Design #1576 (In Progress): cmp for machine integers

Redesign @cmp@ for machine integers so that it works in all cases.
Note that C++20 already @std::cmp_equal@, @std:... John Abbott

15:29 CoCoALib Design #925: MachineInt or long for args which are indices (yet again)

I checked that NTL happily uses @long@ for indices into matrices.
So it is reasonable for us to use @long@ for "indi... John Abbott

15:00 CoCoALib Design #1572: Use noexcept

After discussion with Anna:
* *(A)* a fn which could throw (but only via @CoCoA_ASSERT@) may be declared @noexcept@
... John Abbott

06 Feb 2021

22:00 CoCoALib Design #1572 (Resolved): Use noexcept

I have checked all files which I think might benefit from *@noexcept@*, and have changed most functions which can be ... John Abbott

05 Feb 2021

15:41 CoCoA-5 Bug #1216: RationalSolve: gives wrong answer

I am wondering about changing the return value of @RationalSolve@ into a record, _e.g._
*currently* we get... John Abbott

04 Feb 2021

21:05 CoCoA-5 Bug #1216: RationalSolve: gives wrong answer

I have modified my copy of the code. It now behaves more "predictably".
*@RationalSolve@* now searches only for _... John Abbott

14:49 CoCoALib Design #1572 (In Progress): Use noexcept

I am not sure whether a function which has a local static variable can be @noexcept@.
I suppose, so long as the loca... John Abbott

03 Feb 2021

18:20 CoCoALib Bug #1575 (New): DynamicBitset missing arg checks

I have just looked at the code for @DynamicBitset@ (with the intention of putting in @noexcept@),
and noticed that s... John Abbott

18:18 CoCoALib Feature #1419: DynamicBitset::IamAll1s

I think it might be tricky because inside the loop you need to check if you are at the last position, whereas the new... John Abbott

17:48 CoCoA-5 Bug #1574: ApproxSolveTF

I have set the target version as 5.3.6, but maybe it could be postponed?
It is a bit strange that the solution [0,... John Abbott

17:46 CoCoA-5 Bug #1574 (New): ApproxSolveTF

@ApproxSolveTF@ is not documented. Maybe that is a good thing...... John Abbott

17:26 CoCoA-5 Bug #1216: RationalSolve: gives wrong answer

I now think it might be better to avoid the "clever" function @RationalSolve@ which tries to guess whether it should ... John Abbott

02 Feb 2021

17:04 CoCoALib Design #934 (In Progress): MachineInt: change semantics?

There is a second impl of @MachineInt@ in the current sources. The impl was not complete (but it is now).
However... John Abbott

31 Jan 2021

10:43 CoCoA-5 Bug #1216: RationalSolve: gives wrong answer

Bernhard Andraschko reportes the following:... John Abbott

30 Jan 2021

20:21 CoCoALib Bug #1570 (Feedback): FloatStr sometimes produces NUL chars

John Abbott

18:47 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

I think everything is nearly sorted out now: the example in comment 8 now finds no problems (even over a much wider r... John Abbott

20:17 CoCoA-5 Bug #1573: ApproxSolve: very imprecise

The example was deliberately chosen to be hard/troublesome. Making the parameters @D@ and/or @N@ larger almost surel... John Abbott

19:48 CoCoA-5 Bug #1573 (Closed): ApproxSolve: very imprecise

I have found an example where @ApproxSolve@ gives very imprecise solutions:... John Abbott

29 Jan 2021

20:19 CoCoALib Design #1572: Use noexcept

Maybe not many functions are applicable _e.g._
* the fn must not call a fn which is not @noexcept@ (with args whic... John Abbott

20:18 CoCoALib Design #1572 (Resolved): Use noexcept

Scott Meyers recommends using *@noexcept@* where it fits naturally.
Check to see where we can use it.
John Abbott

20:16 CoCoALib Design #1511: Use C++14 constexpr

So far I have done the following files: (update list as files are done)
* *@bool3.H@*
* *@config.H@*
* *@DivMask@*... John Abbott

20:12 CoCoALib Feature #152 (Closed): Replace bool3 by tribool

I think the new version is OK now. I have also put in *@noexcept@* where appropriate.
One inconsistency: we can a... John Abbott

15:43 CoCoA-5 Feature #1174 (Closed): package of a function --> of an identifier!

Anna Maria Bigatti

15:42 CoCoALib Bug #1571: ker_H needs care

some verbosity has already been included in the file @HomomorphismOps.C@
Anna Maria Bigatti

15:40 CoCoALib Bug #1571 (New): ker_H needs care

The function @ker_H@ is not properly developed/documented.
In particular, there are problems for... Anna Maria Bigatti

15:27 CoCoALib Bug #1484 (Feedback): ker bug (quotientinghom for R/ideal())

Anna Maria Bigatti

15:26 CoCoALib Bug #1484: ker bug (quotientinghom for R/ideal())

Anna Maria Bigatti wrote:
> For proper testing I added some verbosity, but I cannot see it.
> [...]
> what am I mi... Anna Maria Bigatti

09:45 CoCoALib Bug #1484: ker bug (quotientinghom for R/ideal())

For proper testing I added some verbosity, but I cannot see it.... Anna Maria Bigatti

12:26 CoCoA-5 Design #1151 (Closed): ConcatList or ConcatLists

John Abbott

12:05 CoCoA-5 Design #1520 (Closed): Replace BOOST_FOREACH by new C++14 range for syntax

John Abbott

12:03 CoCoA-5 Feature #1516 (Closed): substring function

John Abbott

12:00 CoCoALib Design #854: Function MakeTermOrd should be renamed MakeTermOrdMat?

work for me Anna Maria Bigatti

11:59 CoCoA-5 Design #1334: sylvester or SylvesterMat?

cocoa5 manual for @jacobian@ updated now (2021-01) Anna Maria Bigatti

11:52 CoCoALib Feature #958: New function: multiplicity and dim

AnnaM think and close this! Anna Maria Bigatti

11:31 CoCoALib Feature #1488: BuiltIn Interreduce-Function

John Abbott wrote:
> I have commented out @interreduce@.
> I have renamed the files to @SparsePolyOps-interreduced@... Anna Maria Bigatti

11:26 CoCoALib Design #1563 (Closed): BigRat: ctor from machine int

John Abbott

10:00 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

And indeed the defn of @log@ for @BigRat@ is simply... John Abbott

09:56 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

This is not good.
I have increased the factor in the definition of @delta@ to 64: there are still failing cases:
... John Abbott

09:31 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

Here is a simpler failing case:... John Abbott

28 Jan 2021

21:37 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

I have found what is most likely the cause (after tracing through with the debugger).
The problem was in *@FloorLo... John Abbott

20:35 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

Aha! It seems that @FloorLog10@ sometimes give wrong answers... groan.
With luck that is the root cause.
John Abbott

19:48 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

@FloatStr@ simply calls @MantissaAndExponent10@ to do the main conversion.
Indeed *@MantissaAndExponent10@ behaves w... John Abbott

19:25 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

Operating on @10*q@ produces the same mantissa (with NUL) but without exponent.
Operating on @100*q@ produces a cor... John Abbott

19:17 CoCoALib Bug #1570 (In Progress): FloatStr sometimes produces NUL chars

The exponent is wrong by 1: it should be -10.
John Abbott

19:13 CoCoALib Bug #1570: FloatStr sometimes produces NUL chars

The bug is more embarrassing than dangerous...
Don't yet have a simpler failing example.
Of course, it came up ... John Abbott

19:12 CoCoALib Bug #1570 (Closed): FloatStr sometimes produces NUL chars

Here is a concrete example:... John Abbott

26 Jan 2021

13:47 CoCoALib Design #1558: CpuTimeLimit: more frequent clock checks

While looking for examples for my course computer algebra I wanted to use @GBasisTimeout@. Sometimes the curr impl d... John Abbott

22 Jan 2021

20:44 CoCoALib Feature #152 (Resolved): Replace bool3 by tribool

I have updated the code. Maybe the revised impl is cleaner.
Anyway, it all seems to work. The code is so simple, t... John Abbott

17:15 CoCoALib Feature #152 (In Progress): Replace bool3 by tribool

While the impl in BOOST is surely good, I do prefer to keep CoCoALib independent of BOOST (of course, the interpreter... John Abbott

16:22 CoCoALib Slug #1569: IsInRadical too slow (test-RadicalMembership)

Not surprisingly the computation mod p is very quick.
BTW the answer to the computation as given is (almost certai... John Abbott

15:09 CoCoALib Slug #1569 (Closed): IsInRadical too slow (test-RadicalMembership)

From a demo I showed my students...
I computed a "nasty" 0-dim radical, then wanted to show @MinPowerInIdeal@, but i... John Abbott

15:05 CoCoALib Bug #1565 (Feedback): IsInRadical: gives "weird" error

I have modified the code so that it avoid recomputing the "radical helpers".
All tests pass. Will clean and then ch... John Abbott

10:49 CoCoA-5 Design #1151 (Feedback): ConcatList or ConcatLists

John Abbott wrote:
> Personally I find the name @ConcatLists@ more "natural" because it concatenates many lists.
... Anna Maria Bigatti

10:34 CoCoALib Bug #1484: ker bug (quotientinghom for R/ideal())

John Abbott wrote:
> There are two more suspect creations of ideals: line 325 and 347.
> I have changed these too, ... Anna Maria Bigatti

09:58 CoCoA-5 Design #1568 (In Progress): RMap and image: obsolescent?

I thought @Rmap@ was completely obsolete.
It is defined in @coclib.cpkg5@ and exported.
It is also defined in @ra... John Abbott

09:52 CoCoA-5 Feature #531: Package protected variables should know which package protected them

There is a sort of redundancy in package @$anna@ putting a protection reason on the variable @$anna.var@.
It would... John Abbott

08:44 CoCoA-5 Feature #531: Package protected variables should know which package protected them

All done: works for @:=@, @unprotect@ and @define@.
The field @protectionReason@ is actually set, but for the comp... Anna Maria Bigatti

08:31 CoCoA-5 Feature #1174 (Feedback): package of a function --> of an identifier!

I'm now convinced that the only exception to the evaluation of the argument of a function should be @IsDefined@. The... Anna Maria Bigatti

08:23 CoCoA-5 Feature #346 (Feedback): Describe should indicate package name

Anna Maria Bigatti

21 Jan 2021

15:16 CoCoA-5 Bug #1567 (Resolved): Radical in non-zero char

I have found the problem and fixed it. Also done some cleaning inside @radical.cpkg5@
When are we moving this to C+... John Abbott

15:15 CoCoA-5 Bug #1567 (Closed): Radical in non-zero char

... John Abbott

13:46 CoCoA-5 Support #1566 (Closed): What does rad do?

It seems that CoCoA-5 has a function *@rad@*
What does it do? It is not documented.
John Abbott