Activity

John Abbott's activity

From 25 Mar 2018 to 23 Apr 2018

12:30 CoCoALib Slug #1181 (In Progress): CpuTime is costly!: It might be useful to have something like @ProgressReporter@ which sets a flag when a time-limit has been exceeded?
... John Abbott
12:25 CoCoALib Slug #1181: CpuTime is costly!: I found the problem with an _ad hoc_ program to search for 6x6 matrices with large ratio hadamard/det.
In the main l... John Abbott
12:21 CoCoALib Slug #1181 (Closed): CpuTime is costly!: A call to *@CpuTime()@* is quite costly (on my machine with Fedora 25 Linux).
This means that a calls to @CheckFo... John Abbott
11:18 CoCoALib Design #1124: Move examples directory into doc -- or just change makefile?: I have added a dirty hack to @doc/Makefile@ so that @CopyInfo@ can be compiled even when @libcocoa.a@ does not exist
... John Abbott
11:05 CoCoALib Design #1180 (Resolved): BigRat(0) unexpectedly compiles! (calls ctor with mpq_t arg): The impl has been modified:
* @BigInt@ ctor from @mpz_t@ and from @std::string@ now take 2 args, and are @private@; ... John Abbott

17:58 CoCoALib Design #1180: BigRat(0) unexpectedly compiles! (calls ctor with mpq_t arg): Since the ambiguity of @BigInt(0)@ derives from the fact that @std::string@ has an implicit ctor from @char*@, it may... John Abbott
11:59 CoCoALib Design #1180: BigRat(0) unexpectedly compiles! (calls ctor with mpq_t arg): I have replaced the ctor @BigInt(mpz_t)@ by one which requires a second arg (@CopyFromMPZ@), and then changed all cod... John Abbott

20:24 CoCoALib Design #1180: BigRat(0) unexpectedly compiles! (calls ctor with mpq_t arg): The situation is more complicated than I'd like. Here I'll write about @BigInt@, but it applies just as much to @Big... John Abbott
14:34 CoCoALib Design #1180 (In Progress): BigRat(0) unexpectedly compiles! (calls ctor with mpq_t arg): JAA thinks there is little hope that the language rules for C++ will change (in the forseeable future) to forbid an "... John Abbott
14:10 CoCoALib Design #1180: BigRat(0) unexpectedly compiles! (calls ctor with mpq_t arg): The problem turned out to be that *@2/3@* is evaluated by the compiler to produce @0@ (integer division); this is the... John Abbott
14:04 CoCoALib Design #1180 (Closed): BigRat(0) unexpectedly compiles! (calls ctor with mpq_t arg): The following code excerpt compiles, but does not do what I expected:... John Abbott
18:01 CoCoALib Design #1124: Move examples directory into doc -- or just change makefile?: Anna now likes the idea.
It may also help solve nicely a silly but annoying problem with the compilation of @CopyI... John Abbott

15:11 CoCoALib Feature #1176: interval arithmetic: There is an interval arithmetic sublibrary in the BOOST distribution.
The problem with depending on an external libr... John Abbott
13:41 CoCoALib Feature #1176 (In Progress): interval arithmetic: Implement interval arithmetic (for intervals with rational end points).
Some software libraries already implement ... John Abbott
14:26 CoCoA-5 Bug #1171: RealRoots: first point is sometimes wrong?: I suggest a function with the following semantics:
* call *RealRootsSmallValue(f, eps)*
* result is a list of close... John Abbott
14:19 CoCoA-5 Bug #1171: RealRoots: first point is sometimes wrong?: It is not as simple as I first thought. While the first order approximation I mentioned in comment 3 is correct, it ... John Abbott

11:52 CoCoALib Feature #1173: Upper bound for value of poly in an interval: A while ago I read an article about this (perhaps "evaluating a polynomial over an interval"?). I no longer recall m... John Abbott
11:49 CoCoALib Feature #1173 (New): Upper bound for value of poly in an interval: Write a function which accepts a (univariate) polynomial *f* (with rational coeffs), and an interval *[a,b]* with rat... John Abbott
11:34 CoCoA-5 Bug #1171 (In Progress): RealRoots: first point is sometimes wrong?: One can estimate the "stability" of the root by computing the value of the derivative at that root. By Taylor expans... John Abbott

12:20 CoCoALib Slug #1170 (In Progress): SmoothFactor: slow when a factor is found: I have found the slug: I had activated the "clever idea" of testing for @IsProbPrim@ after a factor has been bound, *... John Abbott

20:25 CoCoALib Slug #1170 (Closed): SmoothFactor: slow when a factor is found: Consider the following:... John Abbott

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