Mathematical reasoning approaches can be a useful tactic when coding. That may not lead to statements worth enshrining, but that's also not necessary.
Thanks, -- Raul On Sat, Jun 16, 2018 at 9:06 AM Henry Rich <henryhr...@gmail.com> wrote: > > Certainly, J doesn't do math. The question is, Is the executable > notation mathy enough that you can reason mathematically about the > computations? I haven't been able to, but maybe someone could find a > set of transformations that is enough for progress in this area. > > On your session-log problem: how about a script to take the session log, > find the lines beginning with 3 spaces, treat the rest as results, and > either create the assertions automatically or execute the sentences and > compare them against the results? > > Henry Rich > > On 6/16/2018 7:18 AM, Ian Clark wrote: > > Thanks, Henry. > > > > Yes… it's all very much not obvious to me too. > > > > I was going to mention NuVoc: > > http://code.jsoftware.com/wiki/Vocabulary/ampdot — but I felt ignorance > > would suit me better. > > > > How to present theorems (propositions?) in J would be good to standardize. > > How to prove them (run them?) even better. > > > > Right now I'm writing test scripts and I'm bog-eyed with typing out assert > > (".phrase) -: (result) over and over again in multifarious forms from an > > extensive session log. Every six months I devise a new solution to this > > perpetual problem – and six months later I reckon it's a dog! > > > > Until that's sorted, I can't pretend to myself J does math. J does > > calculations. > > > > Ian > > > > On Sat, Jun 16, 2018 at 3:35 AM, Henry Rich <henryhr...@gmail.com> wrote: > > > >> It's a theorem: > >> > >> [x] >@(f each) y > >> > >> [x] >@(f&.>) y > >> > >> [x] >@((<@:f)&>) y > >> > >> [x] (>@(<@:f)&> y > >> > >> [x] (>@:<)@:f&> y > >> > >> [x] f&> y > >> > >> [x] (f every) y > >> > >> > >> Some of these steps are very much not obvious IMO. And you have to get > >> the rank of each right, that is, use the NuVoc definition of &. rather than > >> the Dictionary one. > >> > >> Henry Rich > >> > >> > >> On 6/15/2018 8:30 PM, Ian Clark wrote: > >> > >>> I've checked Chapter 1 off, but that's only to say I've checked out the > >>> code and verified it gives the results claimed. I didn't see it as my job > >>> to rewrite the treatment to make it clearer – which I can't do anyway > >>> without being sure what the author is trying to convey. > >>> > >>> I must confess that first section completely baffles me. I cannot see how > >>> to relate the "general rule" to actual examples of J code, although the > >>> article goes on to do just that … it seems. Does the "rule" represent real > >>> working J code? – even in a generic sense? Is it even true? (Theorems have > >>> to be true, but rules only have to be obeyed.) If it isn't always true, am > >>> I to understand it as a rule-of-thumb?And if it is in fact universally > >>> true, what procedure must I, the novice reader, follow in order to convert > >>> the "generics" into "specifics" to verify the fact? > >>> > >>> I'd be grateful for someone to cast light on the matter. Failing which, > >>> maybe I ought to remove my green checkmark, stand aside to let someone > >>> else > >>> scratch their head over it. > >>> > >>> On Sat, Jun 16, 2018 at 12:41 AM, David Lambert <b49p23t...@gmail.com> > >>> wrote: > >>> > >>> 50 Shades of j chapter 1 now says that rule is completely general. I'm > >>>> somewhat weak on j transformations and proofs, although what was there > >>>> was > >>>> incorrect because of a counterexample: > >>>> > >>>> > >>>> every=.&> NB. uses compose > >>>> each=.&.> NB. uses under > >>>> rule =: (f every) -: >@(f each) > >>>> > >>>> NB. Is completely general? > >>>> > >>>> > >>>> thank you, Dave > >>>> > >>>> ---------------------------------------------------------------------- > >>>> For information about J forums see http://www.jsoftware.com/forums.htm > >>>> > >>> ---------------------------------------------------------------------- > >>> For information about J forums see http://www.jsoftware.com/forums.htm > >>> > >> > >> --- > >> This email has been checked for viruses by AVG. > >> https://www.avg.com > >> > >> > >> ---------------------------------------------------------------------- > >> For information about J forums see http://www.jsoftware.com/forums.htm > >> > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
