> I'm at a point where I would like to learn how to write GUIs in J and how to write visually oriented J programs (such as stock market charting programs). I think it may be challenging because, from my initial investigating, there seems to be *extremely* little information (including coding samples) available about these aspects of J programming.
In the Jqt session, examples of gui code are at: Help|Studio|Qt Demos Help|Studio|Showcase Tools|Package Manager The Qt interface is documented starting from page https://code.jsoftware.com/wiki/Guides/Window_Driver On Sun, May 16, 2021 at 10:36 PM HH PackRat <hhpack...@gmail.com> wrote: > Hi, Raul! > > On 5/16/21, Raul Miller <rauldmil...@gmail.com> wrote: > > You left out your example data for 'filer', but you gave enough detail > > that I think I can see what you are trying to do. > > The following (which I did show) was the untransposed original > version, downloaded from Yahoo Finance: > > Date Open High Low Close Volume > ┌──────────┬──────┬──────┬──────┬──────┬────────┐ > │2020-03-06│126.70│128.33│124.52│127.73│8193300 │ > ├──────────┼──────┼──────┼──────┼──────┼────────┤ > │2020-03-09│120.16│122.41│117.28│117.81│10757500│ > ├──────────┼──────┼──────┼──────┼──────┼────────┤ > │2020-03-10│122.78│124.88│115.76│124.77│11410700│ > ├──────────┼──────┼──────┼──────┼──────┼────────┤ > │2020-03-11│121.01│122.58│116.38│117.97│8446500 │ > ├──────────┼──────┼──────┼──────┼──────┼────────┤ > │2020-03-12│109.65│109.80│102.28│102.81│12512700│ > └──────────┴──────┴──────┴──────┴──────┴────────┘ > > What I did then was to transpose it (and called it filer = file r) and > applied the following instructions which retained only the Date, High, > Low, and Close data: > > filer=. 5 {. filer > filer=. 1 0 1 1 1 # filer > > These were followed by the J code I showed in my previous email. > > > That said, I think that I would split this up into two different > routines: > > > > One routine would deal with unpacking the "rows" (or "inverted > > columns) from your data and amending the result. (And possibly either > > converting back to character or ensuring that both character and > > numeric arguments are supported or possibly not - for now, I'll follow > > the pattern from your example.) > > > > The other routine would deal with the numeric "rescaling". We could > > either have different routines here (one for each different kind of > > rescaling) or we could use a switch statement and pack them all > > together like you did. Either way works. This routine would be an > > argument for the other routine. (So the other routine would be an > > adverb.) > > ... > > hiloclose=: 0 0 1 1 1 0 > > > > amender=:{{ > > ndx=. I.x NB. index vector from bit vector > > update=. u 0&".@> x#y > > (<"0 update) ndx} y > > }} > > > > rescaler=:{{ > > select. pricetype=. x > > case. 1 do. y > > case. 2 do. 10 * %: y > > case. 3 do. 100 * 10 ^. y > > end. > > }} > > > > Example use: > > hiloclose 1&rescaler amender filer > > hiloclose 2&rescaler amender filer > > hiloclose 3&rescaler amender filer > > ... > > Now... of course, you might actually want to avoid the amends that I > > assumed you wanted from your textual description. Or you might want > > other things to be different. So this is only an approximation of what > > you might do. > > ... > > And, of course, rather than have the three different rescaling verbs > > be 1&rescaler 2&rescaler and 3&rescaler you might instead give each of > > them a significant name. > > > > Still... perhaps this would be useful to you. > > Thanks so much, Raul, for your response! I'm 75 and continue to learn > new things from replies to questions I've posed to this J programming > group. I have always loved learning during my entire life so far, and > J is a delightful challenge for my mental skills. Older folk like me > often work crossword puzzles or Sudoku to keep their minds sharp--I do > J programming for various computer software challenges! I programmed > as a hobby from 1975 to 2009, using various versions of BASIC over the > years. (I owned an original MITS Altair 8800, for which Bill Gates > and Paul Allen wrote a BASIC interpreter and thus started Microsoft. > Subsequently, I owned an Amiga 1000, and multiple IBM PC clones in > succeeding years.) In 2006 my library's IT department head suggested > that I might take a look at J, and, as they say, the rest is history. > > Although I'm now generally comfortable programming in J (except for > occasional stumpers for which I need to ask for help in this group), > I'm at a point where I would like to learn how to write GUIs in J and > how to write visually oriented J programs (such as stock market > charting programs). I think it may be challenging because, from my > initial investigating, there seems to be *extremely* little > information (including coding samples) available about these aspects > of J programming. > > Again, thanks so much, Raul! > > Harvey > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
