Here's an illustration:
0 1 0 1 0 0 # 1 2 3 4 5 6
2 4
0 1 0 1 0 0 #inv 2 4
0 2 0 4 0 0
#inv is a [right] inverse operation for #, but since information has
been lost, it uses fill to represent the items at the lost positions.
I hope this helps,
--
Raul
On Thu, Jun 21, 2012 at 11:27 AM, David Vaughan <purpleblue...@gmail.com> wrote:
> Thanks, this seems to work, however I am a little confused about what #inv
> (#^:_1) actually does - could you explain that please?
>
> Thanks.
>
> On Thu, Jun 21, 2012 at 4:02 PM, Raul Miller <rauldmil...@gmail.com> wrote:
>
>> Here's one approach:
>>
>> OTHER=: >,{;~1 -.~i.10
>> MASK=: (#~ 8=+/"1) #:i.2^10
>>
>> ,/MASK ([ + -.@[ #inv ])"1/ OTHER
>>
>> --
>> Raul
>>
>> On Thu, Jun 21, 2012 at 10:51 AM, David Vaughan <purpleblue...@gmail.com>
>> wrote:
>> > Hi, I'm trying to generate all permutations of length 10 with eight 1s
>> and two other digits (not 1s).
>> > For example,
>> > 1 1 1 1 3 1 4 1 1 1
>> > 5 1 1 1 1 9 1 1 1 1
>> > ...
>> >
>> > Could anyone point me in the right direction?
>> >
>> > Many thanks.
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