Yeah, I was solving the wrong problem. Never mind.
Henry Rich
On 1/17/2012 12:19 PM, Roger Hui wrote:
> In 0.2 tidr x=:0 3 0.3 3.2 0.6 2 2.3 2.6 3, an index of 8 as the index of 3
> seems an usual result.
>
>
>
> On Tue, Jan 17, 2012 at 4:49 AM, Henry Rich<henryhr...@nc.rr.com> wrote:
>
>> Does this work? Could be extended to negative values of y.
>>
>> NB. Dyad, giving i.!.x~ y for large x. y must be nonnegative
>> tidr =. tolerantidotreflex =. ((% -.)~ I. ]) { /:@]
>> 0.2 (tidr ,: ]) 0 3 0.3 3.2 0.6 2 2.3 2.6 3
>> 0 8 2 8 2 7 7 1 8
>> 0 3 0.3 3.2 0.6 2 2.3 2.6 3
>> 0.5 (tidr ,: ]) 0 3 0.3 3.2 0.6 2 2.3 2.6 3
>> 0 7 2 7 2 7 7 7 7
>> 0 3 0.3 3.2 0.6 2 2.3 2.6 3
>>
>> Henry Rich
>>
>> On 1/16/2012 2:37 PM, Roger Hui wrote:
>>> You can use ": as part of the hashing function and yes you do have to
>> hash
>>> x*1-t and x%1-t .
>>>
>>>
>>>
>>> On Mon, Jan 16, 2012 at 11:19 AM, Raul Miller<rauldmil...@gmail.com>
>> wrote:
>>>
>>>> If hashing would work, then keying on ": would work. I expect though
>>>> that I would need to hash at least twice (adding epsilon before the
>>>> second hash) and I expect that I would need to do something similar if
>>>> I used ":
>>>>
>>>> --
>>>> Raul
>>>>
>>>> On Mon, Jan 16, 2012 at 2:14 PM, Roger Hui<rogerhui.can...@gmail.com>
>>>> wrote:
>>>>> Hashing has expected O(n) time.
>>>>>
>>>>>
>>>>>
>>>>> On Mon, Jan 16, 2012 at 11:11 AM, Raul Miller<rauldmil...@gmail.com>
>>>> wrote:
>>>>>
>>>>>> I think that the "monster case" would be a case where all values are
>>>>>> similar enough that they all map to the same index but different
>>>>>> enough that they cannot be recognized as literal equivalents.
>>>>>>
>>>>>> In the case I am currently interested in, the original values would be
>>>>>> 32 bit floating point numbers and only a relatively few bits of the
>>>>>> available precision would allow values to be treated as "tolerantly
>>>>>> equal". This would suggest that the size of the "monster case" is
>>>>>> limited based on the number of bits being ignored.
>>>>>>
>>>>>> So, in principle at least, this should limit the size of the
>>>>>> "quadratic part" of the problem, for the cases I am trying to address.
>>>>>>
>>>>>> --
>>>>>> Raul
>>>>>>
>>>>>> On Mon, Jan 16, 2012 at 12:04 PM, Roger Hui<rogerhui.can...@gmail.com
>>>
>>>>>> wrote:
>>>>>>> The paper I cited, *Hashing for Tolerant
>>>>>>> Index-Of<http://www.jsoftware.com/papers/Hashing.htm>
>>>>>>> * , presents a "monster" that defeats a sorting algorithm. (Defeat
>>>> in
>>>>>> the
>>>>>>> sense of causing it take quadratic time.)
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Mon, Jan 16, 2012 at 8:07 AM, Henry Rich<henryhr...@nc.rr.com>
>>>>>> wrote:
>>>>>>>
>>>>>>>> You can sort the lists and then compare adjacent values; find
>>>>>>>> superfluous ones; then i.!.0 to find them in the original list.
>>>>>>>>
>>>>>>>> A tricky part is that proximity is not a transitive property. If
>> the
>>>>>>>> tolerance is 2, and the data is
>>>>>>>>
>>>>>>>> 1 2 3 4 5 6 7
>>>>>>>>
>>>>>>>> what should the result of the i.~ be?
>>>>>>>>
>>>>>>>> Henry Rich
>>>>>>>>
>>>>>>>> On 1/16/2012 10:06 AM, Raul Miller wrote:
>>>>>>>>> First: I like Roger Hui's response. And, in essence, it's doing
>>>>>>>>> exactly what you suggest. However, this requires comparing every
>>>>>>>>> number in the left list with every number in the right list. I am
>>>>>>>>> currently pondering algorithms which rely on I. so that when the
>>>> lists
>>>>>>>>> are long computation times are still reasonable (perhaps with
>>>> 100000
>>>>>>>>> members in each list).
>>>>>>>>>
>>>>>>>>> Second: I would want the three PI values in my original message
>>>> to be
>>>>>>>>> treated as equal. I want to be able to specify a magnitude of
>>>>>>>>> acceptable difference which is greater than any of the differences
>>>> in
>>>>>>>>> that data sample.
>>>>>>>>>
>>>>>>>>> FYI,
>>
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