up=: 3 :'UP=:y' NB. temp result cache
xx=: (<"1) 15 3 $ 12 | 45 ?. 200
yy=: (<"1) 10 4 $ 12 | 40 ?. 60
up I.@:-. each (<"1)(,. >{:each xx) i."1 >{.each yy
+---+-+-+-++-+---+-+++-+-++-----++
|5 9|2|6|8||2|5 9|2|||8|0||1 4 7||
+---+-+-+-++-+---+-+++-+-++-----++
(,. (>(#) each UP) # xx) ,. (> ( 0<# ) each , > ({&yy) each UP) # , > ({&yy)
each UP
+------+---------+
|2 6 7 |7 7 0 5 |
+------+---------+
|2 6 7 |7 1 3 3 |
+------+---------+
|7 6 5 |5 11 8 8 |
+------+---------+
|8 6 0 |0 0 9 3 |
+------+---------+
|4 2 4 |4 9 5 8 |
+------+---------+
|8 10 5|5 11 8 8 |
+------+---------+
|6 11 7|7 7 0 5 |
+------+---------+
|6 11 7|7 1 3 3 |
+------+---------+
|7 10 5|5 11 8 8 |
+------+---------+
|9 2 4 |4 9 5 8 |
+------+---------+
|11 8 6|6 11 1 10|
+------+---------+
|0 5 10|10 8 8 1 |
+------+---------+
|0 5 10|10 11 4 3|
+------+---------+
|0 5 10|10 4 3 7 |
+------+---------+
version that drops leading item from yy,
(,. (>(#) each UP) # xx) ,. (> ( 0<# ) each , > ({&yy) each UP) # }. each , >
({&yy) each UP
----- Original Message ----
From: Yuvaraj Athur Raghuvir <[EMAIL PROTECTED]>
To: Programming forum <[email protected]>
Sent: Sunday, October 22, 2006 9:26:05 PM
Subject: Re: [Jprogramming] Re: Using position-match array to generate result -
eliminate the for loop
Pacal, the solution proposed has a problem as it does not scale right.
Looks like there is an assumption on the shape somewhere.
Let me call the rajoin you have proposed as rajoin1.
rajoin1 =: 4 : '(x ,. ]) (({: |: x) i.~ ({. |: y)) { {: |: y'
Now, try this:
x =. 15 3 $ 12 | 45 ?. 200
y =. 10 4 $ 12 | 40 ?. 60
x rajoin1 y
|index error: rajoin1
| (x,.])(({:|:x)i.~({.|:y)) {{:|:y
However,
x rajoin y
+----+--+-------+
|2 6 |7 |7 0 5 |
+----+--+-------+
|2 6 |7 |1 3 3 |
+----+--+-------+
|7 6 |5 |11 8 8 |
+----+--+-------+
|8 6 |0 |0 9 3 |
+----+--+-------+
|4 2 |4 |9 5 8 |
+----+--+-------+
|8 10|5 |11 8 8 |
+----+--+-------+
|6 11|7 |7 0 5 |
+----+--+-------+
|6 11|7 |1 3 3 |
+----+--+-------+
|7 10|5 |11 8 8 |
+----+--+-------+
|9 2 |4 |9 5 8 |
+----+--+-------+
|11 8|6 |11 1 10|
+----+--+-------+
|0 5 |10|8 8 1 |
+----+--+-------+
|0 5 |10|11 4 3 |
+----+--+-------+
|0 5 |10|4 3 7 |
+----+--+-------+
]x
2 6 7
7 6 5
8 6 0
4 2 4
9 4 9
8 10 5
6 11 7
7 10 5
4 11 3
2 1 9
9 2 4
11 8 6
11 0 1
0 5 10
5 10 11
]y
6 11 1 10
10 8 8 1
5 11 8 8
2 0 1 5
10 11 4 3
7 7 0 5
0 0 9 3
10 4 3 7
4 9 5 8
7 1 3 3
On 10/23/06, Pascal Jasmin <[EMAIL PROTECTED]> wrote:
> this will work if y is sorted (easily fixed if not) and indexed continuously
> (left column) from 1 to #y
>
> (x ,. ]) (1 -~ {: |: x) { {: |: y
>
> otherwise, we need to make an indexlookup verb (just i.~) as the left
> argument for { .
>
> (x ,. ]) (({: |: x) i.~ ({. |: y)) { {: |: y
> rajoin =: 4 : '(x ,. ]) (({: |: x) i.~ ({. |: y)) { {: |: y'
>
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