Here's an alternative to 'alternative'
]A=:2 8$ 0 0 1 0 0 0 0 1 1 0 0 0 1 0 0 0
0 0 1 0 0 0 0 1
1 0 0 0 1 0 0 0
]B=:2 5$1 0 0 0 1 0 1 1 0 0
1 0 0 0 1
0 1 1 0 0
alt=: 13 :'(-:((2 2$0 1 1 0)$~#))(|: y /:y) -. 0 0'
alt
[: (-: ((2 2$0 1 1 0) $~ #)) 0 0 -.~ [: |: /:~
alt A
1
alt
Raul wrote:
> Anyways, the definition which is relevant when cap is the left tine of
> a fork is a passive definition, and not an imperative definition. And
> making this distinction -- that it's being used passively -- seems
> worthwhile.
I responded:
> There are several issues with this i
Raul wrote:
> Anyways, the definition which is relevant when cap is the left tine of
> a fork is a passive definition, and not an imperative definition. And
> making this distinction -- that it's being used passively -- seems
> worthwhile.
There are several issues with this interpretation.
Here's another option: convert the two rows into one using base 2, discard
the ones that are 0, and check if the remaining ones are 1 2 1...
I borrowed the sort in Raul's solution so that they must be in that order,
not 2 1 2... .
alternate =: (-: 1 2$~$)@:(0 -.~ #.@|:)@:/:~
Note that we don't ha
I like to think of Cap [: as a left identity element for the tree
representation of a fork.
f g h is
g
f h
and [: g h is
g
h
Sent from my iPad
On Jul 27, 2012, at 8:10 AM, Raul Miller wrote:
> On Thu, Jul 26, 2012 at 7:43 PM, Dan Bron wrote:
>> In a draft, I had originally written
Another approach?
alternates =: [: -. 1 e. [: +/ 0 1 |."0 1 ] #"_ 1~ +./
noAnds =: *./@(-.@(*./))
check =: noAnds *. alternates
--
(B=)
--
For information about J forums see http://www.jsoftware.com/forums.htm
alternate=: 0 1 *./@e.~ , , +/,-&(+/\)/&(\:~)
In other words, we are requiring that the following only gives us 1s and 0s:
[a] The starting data
[b] The sums of the two rows
[c] The difference of the running sums of these two rows (rearranging
the rows so that the leftmost 1 appears in the first
I have an array of shape (2 n), and I want to determine if it has a kind of
alternating pattern, where 1s must appear on alternate rows, when reading from
left to right.
Some examples that do 'alternate':
1 0 0 1 0 1
0 1 0 0 1 0
0 1 0 1 0
1 0 1 0 1
0 0 1 0 0 0 0 1
1 0 0 0 1 0 0 0
Some exampl
On Thu, Jul 26, 2012 at 7:43 PM, Dan Bron wrote:
> In a draft, I had originally written "Meaning its definition is irrelevant".
> I think that sums it up.
Change "definition" to "imperative definition" and that seems reasonable.
Mostly we think of using J verbs using their imperative tense.
Geru
