CoCoA » CoCoALib

03 May 2019

20:36 Bug #1280: Determinant & Inverse of matrix over non integral domain

I'm now wondering what is the difference between @ConstMatrixViewBase::myDet@ and @DenseMatImpl::myDet@... John Abbott

16:35 Bug #1280: Determinant & Inverse of matrix over non integral domain

I'd like to rewrite @ConstMatrixViewBase::myDet@ so that it calls the "fast" impls for small matrices. How to do thi... John Abbott

15:59 Bug #1280 (In Progress): Determinant & Inverse of matrix over non integral domain

Some thoughts about computing the determinant.
There is special case code for:
* small matrices (up to 5x5 incl.)... John Abbott

13:57 Bug #1280: Determinant & Inverse of matrix over non integral domain

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

13:51 Bug #1280 (In Progress): Determinant & Inverse of matrix over non integral domain

CoCoA gives unnecessary errors when computing det or inverse of a matrix over a non-integral domain.
Rectify! John Abbott

14:05 Support #1263: Tidy CoCoALib test directory

I have just checked that running *all* @test-bugNNN@ executables takes about 0.03s on my computer. Since these files... John Abbott

13:45 Feature #303: Rows and Columns of a matrix

I have now added @GetRow@, @GetCol@, @GetRows@ and @GetCols@ to @MatrixOps.txt@
Fixed a couple of minor bugs. Is ... John Abbott

13:24 Feature #303 (Resolved): Rows and Columns of a matrix

I have just implemented @GetRow@, @GetCol@, @GetRows@ and @GetCols@.
Perhaps the names are not ideal, but they are... John Abbott

11:47 Design #1279 (Closed): Tidy up code for matrix determinant

I recently encountered an unexpected error while trying to compute the determinant of a 2x2 matrix over @ZZ/(841)@ wh... John Abbott

11:42 Feature #1278 (New): Port old "clever" code for matrix determinant over ZZ to CoCoALib

In CoCoA-4 there was a "clever" implementation of matrix determinant(over ZZ) based on the paper with Bronstein and M... John Abbott

11:39 Feature #11 (Closed): Bareiss algorithm

This was done ages ago. It has been working trouble-free for over 2 years.
Closing. John Abbott

11:35 Slug #691 (Closed): Matrix determinant over ZZ

I think this was resolved some time ago when I arranged for the code to recognise the case that the entries are all i... John Abbott

30 Apr 2019

17:18 Design #925: MachineInt or long for args which are indices (yet again)

Postponing because there are too many other more pressing issues. Anyway the current code works adequately, so it is... John Abbott

11:51 Feature #813: Implement "elim" in CoCoALib

It would be nice to complete this before the next release! To this end, I have increased the priority... John Abbott

10:54 Feature #1277: Gaussian row reduction

NTL's doc shows just one fn *@gauss@* which accepts 2 args: matrix @M@ and an optional integer @w@ (default is number... John Abbott

10:44 Feature #1277: Gaussian row reduction

The request seems reasonable to me.
Not yet sure what the best design might be, but I suggest the following as a s... John Abbott

10:40 Feature #1277 (Closed): Gaussian row reduction

Julian Danner (Passau) would like CoCoA to offer matrix row reduction via gaussian elimination.
Discuss, design, i... John Abbott

29 Apr 2019

21:05 Support #1276: Release 0.99650

List of principal changes made: *19th november 2019*
* NO LONGER C++03 compatible! We are moving towards C++14 (#89... John Abbott

21:03 Support #1276 (Closed): Release 0.99650

Description
Everything related to making a CoCoALib release:
* Redmine Roadmap: close or postpone issue
* ... John Abbott

18:38 Support #1039 (Resolved): Rename iroot?

I have changed the names into *@FloorRoot@* and *@IsExactFloorRoot@*.
Added *@iroot@* to @obsolescent.H/C@.
Test an... John Abbott

13:25 Support #1039: Rename iroot?

Even though GMP allows negative inputs to its @mpz_root@ function, I like the idea of limiting the number whose root ... John Abbott

13:57 Support #1263: Tidy CoCoALib test directory

I have noticed that there some tests which run quickly (_e.g._ less than 0.01s on my computer), but the compilation t... John Abbott

09 Apr 2019

17:48 Feature #1267: Ideal equality

I'm very uneasy in doing an automatic choice: the "trick" might work out as a slow overhead in a long loop with many ... Anna Maria Bigatti

10:50 Support #1134: Organize better the documentation for CoCoALib

I am postponing this issue. Even though I think it is important, it is likely to need a lot of time; anyway, the doc... John Abbott

05 Apr 2019

16:31 Feature #385: Design new errors using inheritance

This really the same as #743. John Abbott

16:26 Feature #743: Better errors: give supplementary info about the error

It would be nice to have a quiet moment to get this matter properly sorted out.
We really should try to deal with ... John Abbott

16:06 Design #581: C++14: MachineInt

I have modified the subject and description to refer to C++14 instead of C++11.
There is a summary of the integral... John Abbott

15:48 Feature #1218: 32-bit or 64-bit preprocessor macro?

We should check whether this still makes sense with C++14. I should also check on my little 32-bit machine...
John Abbott

15:46 Feature #1197: IsZeroDet: new fn

The idea is simple: compute the det modulo various primes, and if any is non-zero then we know the non-modular det is... John Abbott

12:30 Feature #1267: Ideal equality

A similar trick could be used for ideal membership: if @x@ is not in @I+J@ then it is certainly not in @I@.
John Abbott

04 Apr 2019

21:31 Feature #658: Indets actually in a poly (or vector or matrix)

It seems that there is already an impl in @SparsePolyOps-RingElem@.
There is no doc, no test. Also not exported t... John Abbott

15:16 Feature #1267 (In Progress): Ideal equality

Long sent me one example which wanted to test if a large ideal (in a ring with 36 indets) contained 1. He actually d... John Abbott

15:07 Feature #1269 (New): Ideal Ops: sort-cuts for trivial args?

A colleague here in Passau was disappointed that @intersection(ideal(1), J)@ was taking a long time, even though the ... John Abbott

15:00 Design #1255: Ideals with trivial GBasis

Generators which are monomials are also a special case.
Then one could imagine a more complicated "mixed" situatio... John Abbott