Re: Find maxima in lists of data
- To: mathgroup at smc.vnet.net
- Subject: [mg105795] Re: [mg105772] Find maxima in lists of data
- From: Herman Kuun <oomkoos1 at gmail.com>
- Date: Sat, 19 Dec 2009 06:26:33 -0500 (EST)
- References: <200912181123.GAA16525@smc.vnet.net>
David,
If you only interested in position[s] where maximums occur for a
difference list, this may help.
lst = {1, -2, 3, 1, -3, -2, 3}
Position[Differences[lst], Max[Differences[lst]]] // Flatten
{2, 6}
Best
On Fri, Dec 18, 2009 at 1:23 PM, David <david.leipold at tu-ilmenau.de> wrote:
> I need to find maxima in lists of numerical (measured) data. My basic idea
> is to apply Differences[] to the data and find pairs which differ in Sign[].
> My working solution is:
>
> AllMaxima[lst_] :=
> Flatten[Position[
> Partition[Differences[lst], 2, 1], {x_, y_} /;
> Sign[x] > Sign[y]]];
>
> which behaves as i want. Since it was hard to work this out, i ask myself
> whether i haved overlooked the simple solution. So does anybody know the
> really cool way to achieve this?
>
> Greets!
>
>
--
Best
Herman
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- References:
- Find maxima in lists of data
- From: David <david.leipold@tu-ilmenau.de>
- Find maxima in lists of data