Please be patient while I elaborate;
Ric -
-----
Looking at your solution, I first read up on "Key" (x u /.. y) and
came up with this example:
2 3 2 3 3 (2&|)/. 9 5 7 6 4
1 1 0
1 0 0
which I interpreted as
* group the list on the left (2 2) (3 3 3), then
* partition the list on the right accordingly (9 7) (5 6 4), then
* apply decision between odd (1) and even (0) to the two partitions;
(the zero in the first row is patched).
I then did 'group' and 'tally' on a vector (along an example borrowed
from NuVoc page)
]a=. 7 9 8 7 8 7
7 9 8 7 8 7
(a # /. a)
3 1 2
(~. a) ,:(a # /. a)
7 9 8
3 1 2
to show the frequency of each item.
Replacing 'tally' by 'multiply' and extracting (a)
(a */ /. a)
343 9 64
(*/ /.~) a
343 9 64
I arrived the sought verb
red=. */ /.~
red q: 4200
8 3 25 7
] v=. q: 4200
2 2 2 3 5 5 7
red v
8 3 25 7
Don -
-----
Looking at your solution, I first tried to put it ( in my naive way)
into a verb like
red=. ^/__
red q: 4200
2 3 5 7
3 1 2 1
red v
|syntax error
| red v
The first result looked similar to the above frequency table, which
inspired me to follow this path:
reduc=. 13 : '^/ (~.y) ,:(y#/.y)'
reduc v
8 3 25 7
reduc q:4200
8 3 25 7
reduc=. [: ^/ ~. ,: # /.~
reduc q: 4200
8 3 25 7
reduc v
8 3 25 7
This gives the correct answer but is way from what you suggested ...
Would you kindly explain how you arrived at your code..?
Thanks
-M
At 2016-07-04 21:50, you wrote:
^/__ q:4200
8 3 25 7
On Mon, Jul 4, 2016 at 3:48 PM, Ric Sherlock <tikk...@gmail.com> wrote:
> How's this?
> *//.~ q: 4200
> 8 3 25 7
> On Tue, Jul 5, 2016 at 9:46 AM, Kip Murray <thekipmur...@gmail.com> wrote:
> > Consider
> >
> > q: 4200
> > 2 2 2 3 5 5 7
> >
> > How would you "reduce" this to 8 3 25 7 ?
> > Write the verb red:
> >
> > red q: 4200
> > 8 3 25 7
> >
> > --Kip Murray
> >
> >
> >
> > --
> > Sent from Gmail Mobile
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