Re: Tally
- To: mathgroup at smc.vnet.net
- Subject: [mg86942] Re: Tally
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Thu, 27 Mar 2008 08:15:24 -0500 (EST)
- Organization: The Open University, Milton Keynes, UK
- References: <fsa5eq$adg$1@smc.vnet.net> <fsd6n7$9gh$1@smc.vnet.net>
Jean-Marc Gulliet wrote:
> Armen Kocharyan wrote:
>
>> I'm trying the following:
>>
>>
>> *Dlist = {{{0,1},{0,1}},{{1,0},{1,0}},{{1,0},{0,1}},{{0,1},{1,0}}};*
>>
>> *Tally[Dlist,(#1=== #2) \[Or] *
>>
>> * (#1[[1]][[1]]=== #2[[1]][[2]] \[And] *
>>
>> * #1[[1]][[2]]=== #2[[1]][[1]] \[And] *
>>
>> * #1[[2]][[1]]=== #2[[2]][[2]] \[And] *
>>
>> * #1[[2]][[2]]=== #2[[2]][[1]] )&]*
>>
>>
>>
>> The output is:
>>
>> *{{{{0,1},{0,1}},1},{{{1,0},{1,0}},1},{{{1,0},{0,1}},2}}*
>>
>> instead of
>>
>> *{{{{0,1},{0,1}},2},{{{1,0},{0,1}},2}}*
>>
>>
>>
>> If I remove the last member from DList
>>
>> *Dlist = {{{0,1},{0,1}},{{1,0},{1,0}},{{1,0},{0,1}}};*
>>
>> then I got a correct answer
>>
>> *{{{{0,1},{0,1}},2},{{{1,0},{0,1}},1}}.*
>>
>>
>>
>> Is anything wrong with my original code?
>
>
> Although this does not answer your question, writing your expression as
> follows should help investigating its behavior (assuming, of course, I
> have correctly understood what you try to achieve).
>
> Dlist={{{0,1},{0,1}},{{1,0},{1,0}},{{1,0},{0,1}},{{0,1},{1,0}}};
>
> Tally[Dlist,
> ((#1 === #2) ||
> (#1[[1]] === Reverse@#2[[1]] &&
> #1[[2]] === Reverse@#2[[2]]) &)]
>
> ==> {{{{0,1},{0,1}},1},{{{1,0},{1,0}},1},{{{1,0},{0,1}},2}}
An even more compact way of writing the test function is as follows,
Tally[Dlist, (#1 === #2 || #1 === Reverse /@ #2 &)]
Unfortunately, it still does not solve the issue...
Best regards,
--
Jean-Marc