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Re: Re: Creating a symmetric matrix

• To: mathgroup at smc.vnet.net
• Subject: [mg46917] Re: [mg46889] Re: Creating a symmetric matrix
• From: "Sseziwa Mukasa,,(978) 536-2359" <mukasa at jeol.com>
• Date: Tue, 16 Mar 2004 02:37:20 -0500 (EST)
• References: <c2p9ld$dns$1@smc.vnet.net> <200403130440.XAA15145@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

On Mar 12, 2004, at 11:40 PM, Bobby R. Treat wrote:

> How's this?
>
> symmetric[a_?MatrixQ] :=
>   Array[a[[Min[#1, #2], Max[#1, #2]]] &, {Length@a, Length@a}]
>

It avoids forming the transpose, but it's no faster than those 
solutions on my machine, 60 seconds to process a 2000x2000 array.

Regards,

Ssezi

• References:
  • Re: Creating a symmetric matrix
    • From: drbob@bigfoot.com (Bobby R. Treat)