This is the first announcement for Redick. Originally I wanted to
learn Java as well as learn J, so I started on a Java implementation
of J. Which naturally would be called JJ. And the most famous JJ? Why
JJ Redick. Hence the name Redick.
However, i soon realized that Scheme was a very nice fit for J and it
has a very nice array class as an add-on. So I started on one version
in Scheme and got a good number of monads and dyads written when I
started to run in rank issues.
Deep study of Henry Rich's J for C Programmers forced me to go back to
scratch once again. Now, I have monadic # implemented and implemented
properly:
(define (monad-apply verb noun)
(let* ([v-rank (verb 'get 'rank)]
[n-rank (RankOf noun)]
[r (calc-r v-rank n-rank)]
[f (calc-f (ShapeOf noun) r)]
[n-cells (array-split* noun (frame-length f))]
[framed-cells (result-array f n-cells)]
[v-action (verb 'get 'action)]
)
(if (null? (frame-shape f)) ;; is the frame empty?
;; if so, then apply the verb to the input array as a whole
(v-action framed-cells)
;; otherwise go into each frame and apply verb to data there
(array-index-map!
framed-cells
(lambda indices
(let ([elem (apply array-ref framed-cells indices)])
(v-action elem)))))))
And you can download and play with the installation:
http://redick.metaperl.com
But in case that is too much work, I append the userguide for your
visual consumption. More news later. Thanks for listening!
Redick User Guide
=================
.Load the file `verbs.scm` into the Chicken Scheme interpreter:
......................................................................
/ / /
___ (___ ___ ( ___ ___
| | )| | |___)|___)| )
|__ | / | |__ | \ |__ | /
Version 2.6 - windows-cygwin-x86 - [ dload ptables applyhook ]
(c)2000-2007 Felix L. Winkelmann
#;1> ; loading /home/W049945/prg/redick/scheme/verbs.scm ...
; loading /usr/local/lib/chicken/1/syntax-case.dll ...
; loading /usr/local/lib/chicken/1/syntax-case-chicken-macros.scm ...
; loading /usr/local/lib/chicken/1/pos.scm ...
; loading /usr/local/lib/chicken/1/pos-support.dll ...
; loading alist.scm ...
; loading monads.scm ...
; loading /usr/local/lib/chicken/1/array-lib.dll ...
; loading /usr/local/lib/chicken/1/array-lib-sem.dll ...
; loading /usr/local/lib/chicken/1/misc-extn-list-support.dll ...
; loading /usr/local/lib/chicken/1/misc-extn-condition-support.dll ...
; loading /usr/local/lib/chicken/1/array-lib-hof.dll ...
; loading /usr/local/lib/chicken/1/array-lib-sub.dll ...
; loading /usr/local/lib/chicken/1/box.scm ...
; loading /usr/local/lib/chicken/1/box-support.dll ...
; loading monads/monad-apply.scm ...
; loading monads/Rank.scm ...
; loading monads/RankOf.scm ...
; loading monads/Shape.scm ...
; loading monads/Integers.scm ...
; loading monads/ShapeOf.scm ...
; loading monads/Tally.scm ...
; loading util.scm ...
.....................................................................
.Now build a rank 3 array of shape `2 3 4`
.....................................................................
#;2> (define n (quikary 2 3 4))
#;3> n
#,(array vector ((0 . 1) (0 . 2) (0 . 3)) (((0 1 2 3) (4 5 6 7) (8 9
10 11)) ((12 13 14 15) (16 17 18 19) (20 21 22 23))))
.....................................................................
.Now perform Tally on it with the default infinite rank
.....................................................................
#;4> (Tally n)
2
.....................................................................
As expected, `Tally` tells us that the entire array has 2 items. Let's
use the rank conjunction to produce a version of `Tally` that has
default rank of 2 instead:
.....................................................................
#;5> (define New-Tally-2 (Rank Tally 2))
#;6> (New-Tally-2 n)
#(3 3)
.....................................................................
We told tally that we wanted to process this data as 2-cells stuffed in
a frame of shape 2. And so we got back a result for each frame
position and since there are 3 items in each `3x4` 2-cell, the answer
is 3.
Now let's process our data as a series of 1-cells:
.....................................................................
#;7> (define New-Tally-1 (Rank Tally 1))
#;9> (New-Tally-1 n)
#,(array vector ((0 . 1) (0 . 2)) ((4 4 4) (4 4 4)))
.....................................................................
And finally, let's process the array with rank-0:
.....................................................................
#;10> (define New-Tally-0 (Rank Tally 0))
#;11> (New-Tally-0 n)
#,(array vector ((0 . 1) (0 . 2) (0 . 3)) (((1 1 1 1) (1 1 1 1) (1 1 1
1)) ((1 1 1 1) (1 1 1 1) (1 1 1 1))))
......................................................................
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