Re: [fricas-devel] [PATCH] fix 'sign' in Float and DoubleFloat: sign(0.0)

2017-10-14 Thread oldk1331
On Sat, Oct 14, 2017 at 10:26 PM, Waldek Hebisch wrote: > You write: sign(0.0) should return 0. However, this is debatable. > At least IEEE committee decided differently. Yes, but DoubleFloat of Spad language doesn't say it satisfies IEEE standard:

Re: [fricas-devel] what RetractableTo should actually export

2017-10-14 Thread Martin Baker
On 14/10/17 11:43, oldk1331 wrote: go beyond that and specify axioms seems even more impossible. "Specify axioms"? Do you mean theorem prover? Like Coq or Isabelle? Well the human-readable way to Specify axioms in category theory is diagrams that commute but I suspect the computer-readable

Re: [fricas-devel] [PATCH] fix 'sign' in Float and DoubleFloat: sign(0.0)

2017-10-14 Thread Waldek Hebisch
oldk1331 wrote: > > https://github.com/oldk1331/fricas/commit/3eb98030494c8f84cd87b451a3a713732f777e06.patch > > All tests passed: https://travis-ci.org/oldk1331/fricas/builds/287915875 > (PS: it didn't pass on travis with X11, but pass on > my machine with X11; so I disabled X11 in travis) > >

Re: [fricas-devel] Maybe preview

2017-10-14 Thread Bill Page
On 13 October 2017 at 20:53, oldk1331 wrote: > > You said Boolean has 'Finite', and size()$Boolean is 2. > So Boolean should have Canonical. Canonical is not about the number of values in a domain, it is about how equality is defined. Although Boolean has only two possible

[fricas-devel] [PATCH] fix 'sign' in Float and DoubleFloat: sign(0.0) should return 0

2017-10-14 Thread oldk1331
https://github.com/oldk1331/fricas/commit/3eb98030494c8f84cd87b451a3a713732f777e06.patch All tests passed: https://travis-ci.org/oldk1331/fricas/builds/287915875 (PS: it didn't pass on travis with X11, but pass on my machine with X11; so I disabled X11 in travis) 'sign' is exported from

Re: [fricas-devel] what RetractableTo should actually export

2017-10-14 Thread oldk1331
> go beyond that and specify axioms seems even more impossible. "Specify axioms"? Do you mean theorem prover? Like Coq or Isabelle? -- You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To unsubscribe from this group and stop

Re: [fricas-devel] what RetractableTo should actually export

2017-10-14 Thread Martin Baker
On 14/10/17 02:01, oldk1331 wrote: On Sat, Oct 14, 2017 at 5:16 AM, Bill Page wrote: I am sorry but I do not see how to view this as a natural transformation in the sense of category theory or as the term is applied in Haskell. Could you explain? I mean it