Activity
From 26 Nov 2015 to 25 Dec 2015
23 Dec 2015
-
12:25 CoCoALib Bug #784: threadsafety: Scott Meyers's advice about cached values
- I read a bit in Stroustrup C++ book. There I found a method @std::call_once@ (in @<mutex>@). This method could be a n...
18 Dec 2015
-
16:26 CoCoALib Feature #664 (Resolved): Impl small non-prime finite fields (using logs)
- I have checked in the code I currently have. no doc, no examples, no tests.
An unofficial, simple example (@Fq4.C@ ...
17 Dec 2015
-
16:25 CoCoALib Design #64: submat takes only vector<long>
- John Abbott wrote:
> If we were to adopt the idea of @RowSelect@ and @ColSelect@ then we could offer several signatu... -
- If we were to adopt the idea of @RowSelect@ and @ColSelect@ then we could offer several signatures for @submat@:
* @... -
- John Abbott wrote:
> Here are some other possible suggestions:
I think that's too many, and I think it's not wort... -
- JAA now has a prototype impl which still needs lots of cleaning, but some simple tests pass :-)
I'm hoping to clea...
16 Dec 2015
-
- Scott Meyers advises making interfaces which are "easy to use correctly and hard to use incorrectly"; I think this is...
-
- Here are some other possible suggestions:
* @submat(M, AllRows, ...)@ to select just certain columns
* @submat(M, .... -
- I don't think we should allow other integer types, after all we want to discourage other integer types.
One think I ... -
- -- fixed test anna.cocoa5
-- updated CoCoA-5 manual
-- made suggestion for submat ;-)
10 Dec 2015
-
- It was quite trivial to add the new fns. I have updated the doc too.
Should there be a specific test?
Should imp... -
- I found a case where I needed to obtain the least non-negative residue from a @SmallFpImpl::value@. Doing this via @...
-
- Ignoring the question of the name for @ColCheck@, is it better to have a single fn with a flag to say whether or not ...
-
- I'm also writing *@IsUpperTriangular@*.
*Addendum* (JAA) also @IsLowerTriangular@? Will these go into a "matrix" so... -
- I'm writing another function *HasNegEntry* which checks whether there is a negative entry.
(then we can think of a be... -
- lines 304 and following (@#ifdef@) in @PPOrdering.C@ should be deleted:
we do non require to have a PositiveGrading f... -
- I have just checked in a modified version of @MatrixForOrdering.C@ following Anna's suggestion in comment 2.
Now "...
09 Dec 2015
-
- First bug trapped:
IsPositiveOrd wants @rk(M) == NumRows(M)@.
This function is called when making a term ordering o... -
- JAA believes the root cause is the check that a grading is strictly positive when weakly positive is sufficient.
-
- The current CVS produces 3 failed CoCoALib tests:
@test-MatrixForOrdering1, test-RingWeyl1, test-SparsePolyRing1@
a... -
- JAA will try to implement this before xmas (2015!)
But first some Gluehwein ;-) -
- I wonder whether @CoCoA_THREADSAFE@ is to be just a temporary measure. Presumably at some point practically all comp...
-
- I spoke to Mario this morning about threadsafety in CoCoALib (also thinking about Mario's new code which has just bee...
-
- Bearing in mind the suggestion in issue #142 about using a compile-time switch to indicate whether we want threadsafe...
-
- See the examples in issue #784; I think this should cover many cases.
-
- Adapt Mario's new code so that it is threadsafe (when @CoCoA_THEADSAFE@ is set).
-
- Currently a @MachineInt@ is converted to a @long@ using the function @AsSignedLong@ which includes a check for overfl...
08 Dec 2015
-
- The fact that UIBC needs to be visible in @RingWeyl.C@ is "unfortunate". John and Mario think this may be a symptom ...
-
- With Mario's new code the file @RingWeyl.C@ must include @TmpUIBC.H@ otherwise it does not compile.
This is likely... -
- I have renamed the fns and changed all calls -- well, everything compiles.
Will check doc, then check-in.
-
- A simple interface is: a function which forces computation of a GBasis (without copying the result), and a function w...
-
- Here is a brief "one-way discussion" about some function interfaces: I shall consider just @IsMonomial@, but it is a ...
-
- With Mario's help we have integrated his code into (my copy of) the CoCoA sources.
Some questions have arisen whic...
04 Dec 2015
-
- After skype with Anna: we prefer the nicer sounding names.
So I'll change the names in CoCoALib so that *@Mat@* is a ... -
- John Abbott wrote:
> Perhaps @MakeTermOrd@ or @MakePositiveTermOrdering@, or something similar?
@MakeTermOrd@! -
- I do not much like the names @CompleteToOrd@ and @NewMatCompleteOrd@.
Perhaps @MakeTermOrd@ or @MakePositiveTermO... -
- Currently matrices for gradings must be full rank and have no negative entries.
In princicple we could accept negati...
03 Dec 2015
-
- The CoCoA-5 tests pass as they did before; and the speed test with 20000 indets seemed to go OK. So marking as resol...
-
- I didn't sleep so well this last night (ate something which didn't agree with me), so today's a good day to hack away...
-
- One possible approach is to devise a hash for @symbol@ then just comparing hashes will probably show quickly that the...
-
- Given the cost of converting between a "compressed" format and a "vector" format, it is probably better to represent ...
02 Dec 2015
-
- I had a quick look on Wikipedia for information about sparse matrices. There they distinguished between representati...
-
- A very simple speed test: compute the order of the field/group generator by naive repeated multiplication.
Prototype ... -
- Here are some options for implementing extensions of (prime) finite fields:
* *(A)* use a CoCoALib quotient ring
* ... -
- I have just tried a simplistic speed test (on the "new" computer here in Kassel). The aim was to see how costly it i...
-
- Certainly an explicit quotient ring which is a finite field will be isomorphic to one of "my" finite fields. It migh...
-
- Some (more or less) obvious comments:
* the advantage of having log/exp tables is that some computations can be noti... -
- @IdentityMat@ and @ZeroMat@ are now in @matrix.H@ -- Anna's suggestion.
The args are now @MachineInt@ instead of jus...
01 Dec 2015
-
- I did remember doing something like this.
This was because of a problem in cocoa 4 about 0 in the first row.
I th... -
- I have put this under CoCoALib even though the example comes from the C5 tests, because I think that te real problem ...
-
- The C5 test @primary.cocoa5@ fails because it calls @CompleteToOrd@ on the following matrix:...
-
- Refering to comment 4: I have now removed the signature with 3 args (after speaking to Anna about it).
-
- I shall shortly try to implement the semantics given in comment 4 above.
After speaking to Anna, the idea is that ... -
- I'm mostly interested in a solution which will make most code easy to read (without significant run-time overhead).
... -
- I've just spoken to Mario about this issue (even though he wasn't on the watchers list).
He made some suggestions:
*... -
- It might make sense to allow other types of "condition":
@RangeCheck(arg, PositiveLong)@ or perhaps simply @RangeCh... -
- Mmm, I guess Scott Meyers would not be impressed by a fn @IsInRange@ which takes 3 integer args -- one could guess th...
-
- Checked in the updated code.
Still need: decide fn names, write proper doc!
-
- The documentation for @ElimMat@ and @HomogElimMat@ is largely missing; and the names given in the doc are different f...
-
- I suppose strictly the fns should be called @ElimOrdMat@ and @HomogElimOrdMat@.
Is that a good idea or a not-so-good... -
- Anna suggested change the arg order for @ElimMat@ and @HomogElimMat@ so that the list of indets to elim is the first ...
-
- There are two ways to create a "lex" ordering for @N@ indets:
@NewLexOrdering(N)@ or @lex(N)@.
I wonder whether... -
- I've made the change (plus some very minor cleaning), incl changing the arg names!
Also made the analogous chang... -
- Implemented. No need to change doc (I believe).
A few minor consequential changes.
Will check in shortly.
-
- The same applies to @SetEntry@, @SwapRows@, @SwapCols@, @DeleteRow@, @DeleteCol@.
-
- The pseudo-ctors @ZeroMat@, @IdentityMat@, @MatByCols@, @MatByRows@ have params of type @long@; these should be of ty...
-
- Since the fn @AssignZero@ (for matrices) was no longer used anywhere, and especially since its semantics were rather ...
-
- Here are some other names.
With *SUFFIX* @Mat@:
@ZeroMat@, @IdentityMat@, @BlockMat@, @DiagMat@, @ColMat@, @RowMa...
30 Nov 2015
-
- @IsGreaterThan@?
Or just overwrite @operator>@? -
- Ok, for the Check function (with the function name).
But I 'd rather have (n, lo, hi)... Am I too late to notice ... -
- In prima battuta farei solo @MaxLong@ perche' voglio "scoraggiare" l'uso di @unsigned long@.
Non ti viene i mente ... -
- John Abbott wrote:
> Perhaps the existing @IsInRange@ is not too far from what I want; the real hitch is that an upp... -
- Perhaps the existing @IsInRange@ is not too far from what I want; the real hitch is that an upperbound has to be spec...
-
- Many fns accepting a @MachineInt@ actually want a positive (or non-negative) value.
There is a fn called @IsInRang... -
- Ok, good for operator()!
Still I 'd call the variable @OrdCtor@ ;-) -
- Yes, it should be possible to write @lex(NumIndets)@, but normally it would be enough to write just @lex@ and let the...
-
- Would it be possible to write @PPOrdering O = lex(NumIndets);@?
If not, I fear it might be more confusing.
In fact... -
- We could also have both, but I do not usually like to offer two ways of achieving the same thing... a user might be p...
-
- Currently @PPOrderingCtor@ has a mem fn called @myCtor@ which accepts an integer arg and returns the ordering for tha...
-
- John Abbott wrote:
> @GradingMat@ is used in @hp.cpkg5@ but just for testing whether the grading is "standard"; Ann... -
- John Abbott wrote:
> Does the 0x0 matrix define a term-ordering?
> Do we want to allow users to make a term-orderin... -
- Does the 0x0 matrix define a term-ordering?
Do we want to allow users to make a term-ordering on 0 indets?
JAA think...
27 Nov 2015
-
- Maybe I can do this next week?
-
- Would it be possible to have this by summer 2016?
-
- Just spoken to Anna (via Skype) about the idea of non specifying the ring.
It seems safer for @IdentityMat@ and @Z... -
- @GradingMat@ is used in @hp.cpkg5@ but just for testing whether the grading is "standard"; Anna can you fix this?
-
- I suggest that you try with @degree@ objects containing just a single component, that way the saving as a percentage ...
-
- I note that @test-RingWeyl1.C@ tries to create a an elim mat for no indets. Why? Is that really what it should do?
-
- What should the @ElimMat@ function do in these two limit cases?
* elim no indets
* elim all indets
Note that the...
26 Nov 2015
-
- If there truly is a need to convert a matrix of rationals into a matrix of integers defining the same term ordering, ...
-
- Also converting a (non-neg?) matrix of rationals into a matrix of integers defining an equivalent ordering allows for...
-
- Perhaps the first question should be: do people who build order matrices really start from matrices with rational (no...
-
- In @test-MatrixForOrdering1.C@ the function @NewPositiveMat@ is called with a matrix containing rational (non-integer...
-
- I am pretty convinced that @ZZ@ is the right ring for order matrices in CoCoALib.
That said, I am making sure that... -
- John Abbott wrote:
> The CoCoALib name is @NewMatCompleteToOrd@ while in CoCoA-5 it is @CompleteToOrd@.
> Is this w... -
- John Abbott wrote:
> I suggest that the semantics of @NewMatCompleteToOrd@ be the following:
yes, I agree.
I'm j... -
- I suggest that the semantics of @NewMatCompleteToOrd@ be the following:
* expect as input a matrix @M@ (over ring of... -
- The CoCoALib name is @NewMatCompleteToOrd@ while in CoCoA-5 it is @CompleteToOrd@.
Is this what we want?
-
- What exactly should @NewMatCompleteOrd@ do?
What does its expect as input? And what does it give as output? When d... -
- I have hacked the code: assuming all matrices are over @ZZ@ makes the code a lot simpler. I have added a fn which cr...
-
- Putting into Feedback now that Anna is happy with the C5 manual entry.
I'll add @ILogBase@ to @obsolescent.cpkg5@.
-
- John Abbott wrote:
> I'm still happy with the single combined page for @FloorLog2@, @FloorLog10@, and @FloorLogBase@... -
- I think it is useful. I'll investigate and document it
-
- John Abbott wrote:
> In some ways it would be nice to have a default impl of @AssignZero@; presumably as the mem fn ... -
18:04 CoCoALib Design #825: IsPositiveGrading -- really need 2 signatures?
- John Abbott wrote:
> Just to clarify the semantics:
> * @IsPositiveGrading@ accepts a matrix of integers (error if ... -
- Just to clarify the semantics:
* @IsPositiveGrading@ accepts a matrix of integers (error if entries are not integers... -
- John Abbott wrote:
> What is the difference between @IsTermOrdering@ and @IsPositiveGrading@?
>
> One allows a ze... -
- What is the difference between @IsTermOrdering@ and @IsPositiveGrading@?
One allows a zero-column, the other not?
-
- The fn @IsPositiveGrading@ has 2 signatures:
@IsPositiveGrading(M)@ and
@IsPositiveGrading(M,GrDim)@
Do we reall... -
- Mario now thinks he wants sparse matrices.
We need a clear description of the requirements. -
- JAA thinks that names such as @StdDegRevLexMat@ read more easily than @MatStdDegRevLex@, but the names @MatXYZ@ all a...
-
- There is an incompatibility between the names in CoCoALib and in CoCoA-5 for the pseudo-ctors for matrices for orderi...
-
- Following the principle of "no nasty surprises", I think that @IsTermOrdering@ should do a complete check (incl. corr...
-
- JAA is now convinced that having @OrdMat@ return a "reference" (namely a @ConstMatrixView@) is correct: it was relati...
-
- Could it be useful to have a pseudo-ctor which accepts just the "grading matrix"? The pseudo-ctor would then "auto-c...
-
- Now I wonder why there is the first version of the pseudo-ctor:...
-
- An alternative would be to accept a @record@ as an argument, but this does make the input longer: for instance...
-
- According to the C5 manual, if we want to create a new poly ring with given weights then we must supply a complete or...
-
- The original report did not contain an example of input which produces the unhelpful error message. I think the foll...
Also available in: Atom