Try to remember yourself as a beginner and you want a little more information on reciprocal, the monadic use of % y
The dictionary plunges you into the deep end of the pool: ] a=: i: 3 _3 _2 _1 0 1 2 3 (] ; *) |. a%/a +--------------------------------------+--------------------+ | _1 _1.5 _3 _ 3 1.5 1|_1 _1 _1 1 1 1 1| |_0.666667 _1 _2 _ 2 1 0.666667|_1 _1 _1 1 1 1 1| |_0.333333 _0.5 _1 _ 1 0.5 0.333333|_1 _1 _1 1 1 1 1| | 0 0 0 0 0 0 0| 0 0 0 0 0 0 0| | 0.333333 0.5 1 __ _1 _0.5 _0.333333| 1 1 1 _1 _1 _1 _1| | 0.666667 1 2 __ _2 _1 _0.666667| 1 1 1 _1 _1 _1 _1| | 1 1.5 3 __ _3 _1.5 _1| 1 1 1 _1 _1 _1 _1| +--------------------------------------+--------------------+ 6j2 ": |. a %/ a _1.00 _1.50 _3.00 _ 3.00 1.50 1.00 _0.67 _1.00 _2.00 _ 2.00 1.00 0.67 _0.33 _0.50 _1.00 _ 1.00 0.50 0.33 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.33 0.50 1.00 __ _1.00 _0.50 _0.33 0.67 1.00 2.00 __ _2.00 _1.00 _0.67 1.00 1.50 3.00 __ _3.00 _1.50 _1.00 How many terms will you have to look up before you understand this? Linda -----Original Message----- From: pro [email protected] [mailto:[email protected]] On Behalf Of Linda Alvord Sent: Saturday, March 16, 2013 3:01 AM To: [email protected] Subject: Re: [Jprogramming] Learning J language - initial thoughts Although these choices might be guidelines, Ken always encouraged the teaching of "something". Once a topic is chosen, it is developed using the notation needed. It is the story that is being told that makes the language come alive. The grammar becomes familiar with more use. To me what is needed is short stories in the dictionary which give simple and then more complex examples of the terms being explained. Now that so much information can be delivered so quickly, seven or eight examples could be given of a single verb rather than one example that often requires previous knowledge of many other complicated ideas. If you are reading a dictionary and you find what you want in the simple uses of the word you are looking for, it is not necessary to continue reading possible uses in more complex situations. Also, reading several different uses serves to make the concept more easily understood. Taking away parts of the language does not seem to be the answer. Rather better story telling of topics carefully developed in simple steps chosen because they are needed for that particular story are most helpful. Linda -----Original Message--- From: [email protected] [mailto:[email protected]] On Behalf Of sekm Sent: Saturiday, March 16, 2013 12:00 AM To: [email protected] Subject: Re: [Jprogrammingi] Learning J language - initial thouwhghts Thanks. This was more work than deleting names from Vocabulary, and it is worth it. --Kip Sent from my iPad On Mar 15, 2013, at 10:37 PM, Marshall Lochbaum <[email protected]> wrote: > Here's a stab at this kind of organization, leaving out words for > specific areas of math. Of course these words can be organized in much > the same way. > > BASICS > =. Is (Local) =: Is (Global) > _ Negative Sign / Infinity > : Explicit / Monad-Dyad > " Rank (m"n u"n m"v u"v) > NB. Comment > _9: to 9: and _: Constant Functions > > > ARITHMETIC > - Negate > % Reciprocal >> : Increment > <: Decrement > + • Plus +: Double > - • Minus -: Halve > * • Times *: Square > % • Divide %: Square Root > > <. Floor • Lesser Of (Min) >> . Ceiling • Larger of (Max) > > ^ Exponential • Power ^. Natural Log • Logarithm > > > LOGIC > = • Equal ~: • Not-Equal > < • Less Than <: • Less Or Equal >> • Larger Than >: • Larger Or Equal > > +. • Or *. • And > -. Not > > > LISTS > $ Shape Of • Shape # Tally • Copy > , Ravel • Append ,: Itemize • Laminate > > { • From > {. Head • Take {: Tail • > }. Behead • Drop }: Curtail • > > -: • Match > |. Reverse • Rotate (Shift) > > / Insert • Table > > i. Integers • Index Of > e. Raze In • Member (In) > > /:~ Sort Up \:~ Sort Down > -. • Less > ~. Nub > > > COMPOSITIONS > ^: Power (If) > ~ Reflex • Passive > @ Atop @: At > & Bond / Compose &: Appose > &. Under &.: Under > [ Same • Left ] Same • Right > > > STRINGS > ". Do ": Default Format > a. Alphabet > > > BOXES > < Box > Open > ; Raze • Link > ;: Words > > Marshall > > On Fri, Mar 15, 2013 at 11:00:41PM -0400, Marshall Lochbaum wrote: >> I'll jump in here and point out that words vary massively in their >> potential to confuse. You've taken out >: <: +: -: *: %: , but these >> verbs are dead simple to remember (and, as a bonus, you can do all of >> them at once), and often make reasoning with J a lot easier. I >> couldn't teach J without using these because they are simple monadic >> verbs with easy utility. +/&.:*: is a great way to teach how &.: works. >> +/&.:(^&0.5) is not. >> >> On the other hand there are the words--particularly conjunctions and >> adverbs--that are very difficult to figure out. You've taken out most >> of these, like /. and ;. . I think } and ,. also belong in this >> category. } is, though merely awkward in theory, actually a patchwork >> of corner cases. ,. and to a lesser extent ,: are difficult to get >> right, and I think ,. is better taught as ,"_1 in both valences. >> These are the words that really need to be taken out. Leave the >> technically useless but simple and convenient words alone. >> >> This list looks like it's tending towards an effort to gut as many >> words as possible and make the language look small. I think a better >> approach would be to organize words into a few groups--arithmetic, >> logic, lists, compositions, and heavy mathematics--which contain a >> larger selection of useful operations and stress the symmetry of >> these (why would you take out any of {. {: }. }: when they are easy >> to teach in a group?). Words that are truly confusing and take a long >> time to understand (H. , >> anyone?) would be left out. >> >> Marshall >> >> On Fri, Mar 15, 2013 at 08:15:29PM -0500, km wrote: >>> >>> Here's the latest J core, using additional paring suggested by Raul. >>> >>> I did keep }: because of puzzling things that happen if you use _1&{. >>> instead (giving you a vector instead of a scalar). And I took out GCD . >>> >>> --Kip Murray >>> >>>>> << Usr Pri JfC LJ Phr Dic Rel Voc !: Help Dictionary >>> >>> Vocabulary ( Constants Controls Foreigns Parts of Speech ) >>> >>> = • Equal =. Is (Local) =: Is (Global) >>> < Box • Less Than <. Floor • Lesser Of (Min) <: • Less Or Equal >>>> Open • Larger Than >. Ceiling • Larger of (Max) >: • Larger Or Equal >>> _ Negative Sign / Infinity >>> >>> >>> + • Plus >>> >>> * • Times >>> >>> - Negate • Minus -. Not • Less -: • Match >>> % Reciprocal • Divide >>> >>> >>> ^ Exponential • Power >>> ^: Power (u^:n u^:v) >>> $ Shape Of • Shape >>> >>> ~ Reflex • Passive ~. Nub • ~: • Not-Equal >>> | Magnitude • Residue |. Reverse • Rotate (Shift) >>> >>> >>> >>> >>> : Explicit / Monad-Dyad >>> >>> , Ravel • Append ,. Ravel Items • Stitch ,: Itemize • Laminate >>> ; Raze • Link >>> ;: Words >>> >>> # Tally • Copy >>> >>> ! Factorial >>> >>> / Insert • Table >>> /: • Sort >>> \ Prefix >>> \: • Sort >>> >>> [ Same • Left [: Cap >>> ] Same • Right >>> { • From {. Head • Take {: Tail • >>> } • Amend (m} u}) }. Behead • Drop >>> >>> " Rank (m"n u"n) ". Do • ": Default Format • Format >>> >>> >>> @ Atop @. Agenda >>> & Bond / Compose &. Under (Dual) >>> ? Roll • Deal >>> >>> a. Alphabet a: Ace (Boxed Empty) >>> >>> >>> >>> >>> >>> >>> e. • Member (In) >>> E. • Member of Interval >>> >>> >>> i. Integers • Index Of >>> I. Indices • Interval Index >>> >>> >>> >>> >>> NB. Comment >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>> >>>>> << Usr Pri JfC LJ Phr Dic Rel Voc !: Help Dictionary >>> >>> Sent from my iPad >>> >>> >>> On Mar 15, 2013, at 10:27 AM, Greg Borota <[email protected]> wrote: >>>> >>>> 3) I am not the first to mention this. I wish there was a minimal J >>>> language core documented/available. I see veterans on this forum >>>> saying things like: "I almost never use some of those verbs". Is >>>> there not a minimal J language core targeting general language use? >>>> For example, leaving out specifics like numerical analysis, >>>> statistics, etc. This might help some not drop by the way side. >>>> E.g. http://xprogramming .com/category/j-language/ >>> >>> >>> On Mar 15, 2013, at 3:26 PM, Raul Miller <[email protected]> wrote: >>> >>> ... >>>> >>>> I'd probably also eliminate foreigns from "core". Foreigns are >>>> about as peripheral as you can get. The beginner should probably >>>> be told to start with covers (fread, fwrite, ...). >>> -------------------------------------------------------------------- >>> -- 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 ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
