Re: generalized foldlist problem - part 2
- To: mathgroup at smc.vnet.net
- Subject: [mg69185] Re: [mg69138] generalized foldlist problem - part 2
- From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
- Date: Fri, 1 Sep 2006 06:41:21 -0400 (EDT)
- References: <200608310838.EAA19506@smc.vnet.net> <03162F89-A4A8-4977-A494-E8ADFC4C9003@mimuw.edu.pl> <47EB8B12-D057-4AE3-8534-9B3A0CCCB490@mimuw.edu.pl>
- Sender: owner-wri-mathgroup at wolfram.com
On 31 Aug 2006, at 22:22, Andrzej Kozlowski wrote: > On 31 Aug 2006, at 20:49, Andrzej Kozlowski wrote: >> >> (PS. In answering part 1 I obviously misunderstood your question, >> but I think that was mainly because I do not think your function >> is in any way a "generalisation of Fold", or even of Fold >> [Plus,element,list]. As far as I can see it does not really >> perform any kind of "folding". > > On second thoughts, I withdraw most of that PS. Taking list2= > {1,1,1,...} in your original function, we certainly get a > generalisation of FoldList[Plus,First[list1],Rest[list1]], so the > subject name "generalised foldlist problem" is not entirely > unjustified. However, it seems to me that describing the function > in this way confuses rather then clarifies what the function does > (hence, I think, Jens remarks in reply to your original post and my > comment above). It seems to me that the best description of your > problem is terms of the matrix that you used in part 2. Could you, > perhaps, explain how this problem arose and what you are "really > trying to do"? > > Andrzej Kozlowski > Sorry, wrong again. We need to take list2 = Table[Length[list1], {Length[list1]}] to get a generalisation of FoldList[Plus,First [list1],Rest[list1]]. Andrzej Kozlowski