Finding Maximum without a plot
- To: mathgroup at smc.vnet.net
- Subject: [mg129798] Finding Maximum without a plot
- From: Tim Trudgian <tim.trudgian at gmail.com>
- Date: Thu, 14 Feb 2013 02:11:19 -0500 (EST)
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- Delivered-to: l-mathgroup@wolfram.com
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I should like to find the maximum of Abs[Zeta[1/2 + I*t]]/t^(1/4) for t large, say, t< 10^10. The trouble with NMaximize is that (sometimes) only local maxima are picked up. When plotting, say Plot[Abs[Zeta[1/2 + I*t]/t^(1/4)], {t, 3, 10^5}, PlotRange -> Full] I can see that, around t = 20,000, there is a value above 1.5. This value is not picked up when plotting the same function in the range {t, 3, 10^6}. Does anyone have any solutions other than plotting blocks of 10^k, 10^(k+1)?