Re: Re: Maxima & Minima

*To*: mathgroup at smc.vnet.net*Subject*: [mg53777] Re: [mg53758] Re: Maxima & Minima*From*: DrBob <drbob at bigfoot.com>*Date*: Thu, 27 Jan 2005 05:41:14 -0500 (EST)*References*: <200501240837.DAA28176@smc.vnet.net><ct56fb$eak$1@smc.vnet.net> <200501260937.EAA00242@smc.vnet.net>*Reply-to*: drbob at bigfoot.com*Sender*: owner-wri-mathgroup at wolfram.com

Very nice! (But we don't really know if the glitches ARE glitches, of course.) Bobby On Wed, 26 Jan 2005 04:37:09 -0500 (EST), Ray Koopman <koopman at sfu.ca> wrote: > DrBob wrote: >> Here's a complete list of local extrema in the raw data: >> >> data[[1+Flatten@Position[Partition[data[[All, 2]], 3, 1], >> {a_, b_, c_} /; b < Min[a, c] || b > Max[a, c]]]] >> >> {{0.51, 1.30244}, >> {0.53, 1.3059}, >> {0.54, 1.30544}, >> {0.58, 1.31146}, >> {0.59, 1.31105}, >> {0.66, 1.32175}, >> {0.67, 1.32041}, >> {0.83, 1.81008}, >> {1.11, 0.0324386}, >> {1.71, 1.72145}} >> >> (Too many, if we assume the data is only approximate.) > > That approach works fine (at least with this data) if we widen the > window and look more than one point to the left and right: > > With[{k = 2}, > data[[k + Flatten@Position[Partition[data[[All,2]],2k+1,1], x_List /; > x[[k+1]] < Min[Delete[x,k+1]] || x[[k+1]] > Max[Delete[x,k+1]]]]]] > > will ignore the glitches and give > {{0.83,1.81008},{1.11,0.0324386},{1.71,1.72145}} > > > > -- DrBob at bigfoot.com www.eclecticdreams.net

**References**:**Maxima & Minima***From:*nilaakash@gmail.com (nilaakash)

**Re: Maxima & Minima***From:*"Ray Koopman" <koopman@sfu.ca>