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Re: Find index of maximal element in multi-dimensional array

  • To: mathgroup at smc.vnet.net
  • Subject: [mg73591] Re: Find index of maximal element in multi-dimensional array
  • From: "Dana DeLouis" <dana.del at gmail.com>
  • Date: Thu, 22 Feb 2007 04:41:16 -0500 (EST)

> The output is like this:
> {{5, 4}, 0.921344}

Hi.  One of many ways...

SeedRandom[2]; 
z = Table[Random[], {5}, {6}]; 

Position[z, Max[z]] /. (v_)?VectorQ :> {v, Extract[z, v]}

{{{4, 3}, 0.9585506645732469}}

-- 
HTH
Dana DeLouis
Windows XP & Mathematica 5.2

"Andrew Moylan" <andrew.j.moylan at gmail.com> wrote in message
news:erelbt$7h4$1 at smc.vnet.net...
> Hi all,
> 
> Here's a two-dimensional array of numbers:
> 
> z = Table[Random[], {5}, {6}]
> 
> What's an efficient way of finding the index of the maximal element of
> z? Here's one way:
> 
> Last[Sort[Flatten[MapIndexed[{#2, #1} & , z, {2}], 1],
>   OrderedQ[{#1[[2]], #2[[2]]}] & ]]
> 
> The output is like this:
> 
> {{5, 4}, 0.921344}
> 
> But it's so untidy. Any better ideas?
> 
> Cheers,
> 
> Andrew
> 
>



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