That's kind of difficult to read...
But ... it looks like the BASIC pluk implementation sets up a loop,
reading numbers, and printing lines of text. That doesn't feel right
for J -- it would be nicer to have a textual result that can be used
elsewhere. So, I wrote a pluk which takes a numeric argument along the
lines of what the BASIC pluk supports, and returns a character list
similar to what the BASIC program displays:
This implementation requires that the text of the CREDO file be saved
in the J user directory. (And, if you are copying and pasting from the
pdf, beware that the final line needs to begin with a space character.
When I copied and pasted, that space character was lost.)
Anyways, here's the implementation:
CREDO=: <;._2 (fread '~user/CREDO')-.CR
pluk=: {{ y=.":y assert.*/y e.'0123456789'
r=. y,':'
for_line.CREDO do.A=.;line
len=.(#y)<.A i.' '
wild=. (I.'0'=len{.y),I.'0'=len{.A
if. y */ .=&('0' wild} ])&(len{.]) A do.r=.r,(}.~i.&' ')A end.
end.r
}}
Example use:
pluk '13510'
13510: CREDO IN SPIRITUM QUI CUM PATRE ET FILIO SIMUL ADORATUR AMEN
pluk '13520'
13520: CREDO IN SPIRITUM QUI CUM PATRE ET FILIO SIMUL GLORIFICATUR AMEN
While technically, this approach is somewhat general -- you can
construct numbers which reference sequence, I am not sure how I would
proofread a file, for correctness (for hypothetical files other than
CREDO).
I guess this feels like it's about half way between a compression
system and an indexing system.
I hope this helps,
--
Raul
On Mon, Feb 14, 2022 at 4:28 PM 'Bo Jacoby' via Chat <[email protected]> wrote:
>
> Ric requested thoughts on database structure and asked for examples.
>
> Consider this example.
>
> https://www.dropbox.com/s/gj8r19hd6exyw3s/Norddata89.pdf?dl=0
>
> The database browser is 8 lines of BASIC. I have not converted it into J. I
> have no routine in file handling in J.
>
> The database example is in Latin. The explanation is in Danish.
>
> Have fun!
>
> Thanks. Bo.
>
>
>
>
>
> ----- Videresendt meddelelse -----
>
> Fra: Ric Sherlock <[email protected]>
> Til: Programming JForum <[email protected]>
> Sendt: mandag den 14. februar 2022 02.31.51 CET
> Emne: Re: [Jprogramming] DataFrames in J
>
>
> Hi Pascal,
> From your email examples this looks promising.
> I'll need to spend a bit of time with your repo though to get a better
> understanding of what is going on here & what I think about it.
> Thanks!
>
> On Mon, Feb 14, 2022 at 12:27 PM 'Pascal Jasmin' via Programming <
> [email protected]> wrote:
>
> > updated kv to support inverted tables.
> >
> > https://github.com/Pascal-J/kv/blob/main/kv.ijs
> >
> >
> > output for these functions are near bottom of
> > https://raw.githubusercontent.com/Pascal-J/kv/main/README.md
> >
> > 'Id Name Job Status' kv ,.&.:>"1 |: maybenum each > ','cut each cutLF 0 :
> > 0 NB. from your example
> >
> > 3,Jerry,Unemployed,Married
> > 6,Jan,CEO,Married
> > 5,Frieda,student,Single
> > 1,Alex,Waiter,Separated
> > )
> >
> >
> > A one line dsl version:
> >
> > itdsl kvdsL 'Id Name Job Status `3 6 5 1 ; Jerry Jan Frieda Alex
> > ;Unemployed:CEO:student:Waiter; Married Married Single Separated'
> > NB. note extra garbage spaces
> >
> > In a dictionary, inverted tables are stored as key(fieldname), and
> > associated boxed table (field value that can be longer than 1 char per
> > value).
> >
> > I have an inverted table display (keys as column headers) too. That can
> > optionally filter just the fields you wish
> >
> > A query that retrieves records where Job is 'CEO' or 'student' then
> > displays in IT format
> >
> > itdisp ('CEO;student' padstrmatch 'Job' kvget ]) kvQ it_kvtest_
> >
> > or partial 3 column display without the special ; parsing
> >
> > 'Id Name Job' itdisp1 (('CEO';'student') padstrmatch 'Job' kvget ]) kvQ it
> >
> > kvQ is a "query engine" (too simple to call it that) that takes a boolean
> > function to filter records "on set of properties/fields"
> >
> > Basically an inverted table as a dictionary is a dictionary that only
> > contains the properties corresponding to fields. Because kv can store
> > other dictionaries, if you have additional information to store, it can be
> > in "peer" keys to your IT dictionary.
> >
> >
> >
> >
> > On Sunday, February 13, 2022, 08:49:02 a.m. EST, Ric Sherlock <
> > [email protected]> wrote:
> >
> >
> >
> >
> >
> > Inspired by recent threads, I've started experimenting with a DataFrame
> > structure in J.
> > I began by building off the 'general/misc/inverted' utilities so that a
> > DataFrame is just a 2-row table, where the first row is a list of labels &
> > the 2nd is an inverted table.
> >
> > It can be installed as 'tables/dataframe' from the following github
> > repository: https://github.com/tikkanz/jdataframe
> >
> > The JArrow bindings that Aaron pointed me at a while back represent a
> > similar data structure as a 2-column table where the labels are in the
> > first column and the "columns" are rows in the 2nd column.
> > (https://github.com/tikkanz/JArrow)
> > I think I need to play with both for a while to see which works better.
> >
> > Obviously there is a lot more to do, but I thought I'd share in case anyone
> > has any thoughts, suggestions or wants to help take the idea further.
> > Ric
> > ----------------------------------------------------------------------
> > 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
