On 19/03/16 21:57, Vittorio Giovara wrote:
> On Tue, Apr 21, 2015 at 12:50 PM, Andreas Cadhalpun
> <[email protected]> wrote:
>> On 21.04.2015 02:20, Claudio Freire wrote:
>>> On Mon, Apr 20, 2015 at 9:13 PM, Michael Niedermayer <[email protected]> 
>>> 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 <[email protected]> 
>>>>> wrote:
>>>>>> On Mon, Apr 20, 2015 at 8:32 PM, Andreas Cadhalpun
>>>>>> <[email protected]> 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.
>>
>> Best regards,
>> Andreas
> 
> Is this patch still needed?
> 

Should be ok to merge it.
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