On Tue, Apr 21, 2015 at 06:50:20PM +0200, Andreas Cadhalpun wrote: > On 21.04.2015 02:20, Claudio Freire wrote: > > On Mon, Apr 20, 2015 at 9:13 PM, Michael Niedermayer <michae...@gmx.at> > > wrote: > >> On Mon, Apr 20, 2015 at 09:07:14PM -0300, Claudio Freire wrote: > >>> On Mon, Apr 20, 2015 at 8:59 PM, Claudio Freire <klaussfre...@gmail.com> > >>> wrote: > >>>> On Mon, Apr 20, 2015 at 8:32 PM, Andreas Cadhalpun > >>>> <andreas.cadhal...@googlemail.com> wrote: > >>>>>>>> The long version: > >>>>>>>> > >>>>>>>> ath should approximate the shape of the absolute hearing threshold, > >>>>>>>> so > >>>>>>>> yes, it's best if it really uses the minimum, since that will prevent > >>>>>>>> clipping of the ath curve and result in a more accurate threshold > >>>>>>>> computation. > >>>>>>> > >>>>>>> So you agree with my patch fixing minath? > >>>>>>> Or would you prefer a version with: > >>>>>>> minath = ath(3410 - 0.733 * ATH_ADD, ATH_ADD) > >>>>>> > >>>>>> Well, that's not really closer to the minimum (a few tests with > >>>>>> gnuplot say). > >>>>> > >>>>> Are you sure your plots were done correctly? > >>>>> Because I'm quite sure this is the correct first order approximation > >>>>> of the minimum. > >>>>> > >>>>> For ATH_ADD = 4 this gives 3407.068, which is quite close to Michael's > >>>>> value > >>>>> (3407.080774800152). > >>>> > >>>> I checked the formula several times, but still, I could have made a > >>>> mistake. > >>> > >>> > >>> This is what I did if you want to check it out (maybe you spot the > >>> mistake) > >>> > >>> gnuplot> ath(f,a) = _ath(f/1000.0, a) > >>> gnuplot> _ath(f,a) = 3.64 * f**(-0.8) - 6.8 * exp(-0.6 * (f-3.4) * > >>> (f-3.4)) + 6.0 * exp(-0.15 * (f-8.7) * (f-8.7)) + (0.6 + 0.04 * a) * > >>> 0.001 * f * f * f > >> ^^^^^^^^^^ > >> missing * f > > > > Much better now :) > > > > So yes. I'd say it's a good change. > > OK, patch attached.
applied thanks [...] -- Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB Republics decline into democracies and democracies degenerate into despotisms. -- Aristotle
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