So Henry, can you imagine yourself doing FFT on a sparse hypercube, sparse
because many of the entries are 0?  For this application not having rank
restricted to 63 or less would be nice.




On Sun, Apr 4, 2021 at 8:04 AM Roger Hui <[email protected]> wrote:

> > I haven't used rank beyond 6 that I can recall, if that.
>
> FFT uses a high rank array, a hypercube with shape (>.2^.#x)$2 .  Of
> course, a rank-64 hypercube would blow current computers out of the water.
>
> https://code.jsoftware.com/wiki/Essays/FFT
>
>
>
> On Sun, Apr 4, 2021 at 7:55 AM 'robert therriault' via Programming <
> [email protected]> wrote:
>
>> I haven't used rank beyond 6 that I can recall, if that.
>>
>> I suppose that I could get around the limit by boxing items of a higher
>> rank to reduce them to lower rank and using one verb to manipulate the
>> boxes and another to manipulate the dimensions within the box.
>>
>> What is the performance advantage to setting a boundary?
>>
>>
>> > On Apr 4, 2021, at 07:45, bill lam <[email protected]> wrote:
>> >
>> > What's special about 63? Why not 128, say.
>> >
>> > On Sun, Apr 4, 2021, 9:52 PM Henry Rich <[email protected]> wrote:
>> >
>> >> I propose that the maximum value for a rank, whether of a verb or a
>> >> noun, will be 63.  Minimum verb rank will be _63.
>> >>
>> >> You got a problem with that?
>> >>
>> >> Henry Rich
>> >>
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