Mathematica 9 is now available
Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2010

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

Search the Archive

Re: How to construct symmetric matrix from just a one half matrix

  • To: mathgroup at smc.vnet.net
  • Subject: [mg110393] Re: How to construct symmetric matrix from just a one half matrix
  • From: "Sjoerd C. de Vries" <sjoerd.c.devries at gmail.com>
  • Date: Wed, 16 Jun 2010 05:39:48 -0400 (EDT)
  • References: <hv76li$k4j$1@smc.vnet.net>

fun[m_?MatrixQ]:= m + Transpose[m] - m IdentityMatrix[Length[m]]

or

fun[m_?MatrixQ]:= m + Transpose[m] - UpperTriangularize[m]

or

fun[m_?MatrixQ]:= m + Transpose[m] - DiagonalMatrix[Tr[m, List]]

Cheers -- Sjoerd


On Jun 15, 8:30 am, dragec <culino... at gmail.com> wrote:
> please help me with simple to apply function that will construct
> symmetric matrix from given just a half matrix with diagonal.
> Eg:
>
> From:
> 1  0  0  0
> 2  3  0  0
> 4  9  5  0
> 2  2  3  4
>
> To give:
>
> 1  2  4  2
> 2  3  9  2
> 4  9  5  3
> 2  2  3  4



  • Prev by Date: Re: Simplification question
  • Next by Date: Re: How to construct symmetric matrix from just a one
  • Previous by thread: Re: How to construct symmetric matrix from just a one half matrix
  • Next by thread: Re: How to construct symmetric matrix from just a one half matrix