Re: Find index of maximal element in multi-dimensional array
- To: mathgroup at smc.vnet.net
- Subject: [mg73522] Re: Find index of maximal element in multi-dimensional array
- From: "Norbert Marxer" <marxer at mec.li>
- Date: Wed, 21 Feb 2007 01:42:20 -0500 (EST)
- References: <erelbt$7h4$1@smc.vnet.net>
On 20 Feb., 12:17, "Andrew Moylan" <andrew.j.moy... at gmail.com> wrote: > 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 Hi Andrew You can use Position[z, Max[z]] if you just want the index. Or you can use {Position[z, m = Max[z]], m} if you want both the index and the value. Best Regards Norbert Marxer www.mec.li