I have a non iterative script which seems to work on the test sample.
Can you tell me if it works more generally, please?
H =: 99 NB. can be any large value, like 1e6
L =: _1
D =: H, H, 1, H, 5, H, 8, H, 11, L, L, H, H, 20,3
P =: 1, 1, 1, 2, 4, 2, 1, 1, 1, 1, 1, 1, 2, 1, 2
excP =: (1,L=])<;._1 L,[ NB. exclude L from left arg: P
excD =: (1,L=])<;._1 L,] NB. exclude L from right arg: D
lineup =: -@#{.!.H every]
e =: each each
P( (L~:]) #inv!.L (<"0 each@excD) ;@:(<./@lineup@:(<@(([,+)every))each)
(+/\e)@(}.e)@(<\.each)@excP) D
On Fri, Feb 26, 2016 at 5:19 AM, Henry Rich <[email protected]> wrote:
> No.
>
> The first atom of the array might potentially affect the result in the
> last atom.
>
> I need a method that takes at most a couple of dozen machine instructions
> per atom. Any method that starts a verb on each atom of the array is too
> slow.
>
> Henry Rich
>
> On 2/25/2016 10:35 PM, Brian Schott wrote:
>
>> Does your really fast algorithm start with something like my mask, but
>> instead of a while. loop on the whole array, do you just check to update
>> the indices one above each altered atom of the revised D?
>>
>> On Wed, Feb 24, 2016 at 11:43 AM, Henry Rich <[email protected]>
>> wrote:
>>
>> That looks like the right result.
>>>
>>> Henry Rich
>>>
>>>
>>>
--
(B=)
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