Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2001
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2001

[Date Index] [Thread Index] [Author Index]

Search the Archive

Partitioning 1-D list into 2-D Matrix

  • To: mathgroup at smc.vnet.net
  • Subject: [mg29758] Partitioning 1-D list into 2-D Matrix
  • From: "Krautschik, Chris G" <krautschikc at intel.co.jp>
  • Date: Sat, 7 Jul 2001 02:26:02 -0400 (EDT)
  • Sender: owner-wri-mathgroup at wolfram.com

I have a question of how to best select elements from a list and reformat
the list into a 2D matrix. Here is an example:

b=Range[1,20]
{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20}

I would like to arrange the list into a 2D array of the following form:
{{1, 3, 5, 7, 9}, {2, 4, 6, 8, 10}, {11, 13, 15, 17, 19}, {12, 14, 16, 18,
20}}

Then
bb=Partition[Partition[b,2],5] 
 <<...OLE_Obj...>> 
almost does what I want if you view this array in MatrixForm[]. However, I
would have to somehow get rid of the innner brackets. I am not sure how to
do that with Flatten[].

I could use brute force and select the elements as follows:
 <<...OLE_Obj...>> 
 <<...OLE_Obj...>> 

I have a feeling there is a much better way to do this.

Thanks in advance,
Chris



  • Prev by Date: Re: List-Operations on Heads other than List
  • Next by Date: Re:Map
  • Previous by thread: Re: Opening Directory
  • Next by thread: Re: Partitioning 1-D list into 2-D Matrix