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Re: Possible simple bug in NMaximize


> On 6 Nov 2006, at 19:05, Andrzej Kozlowski wrote:
>
>> 
>> On 6 Nov 2006, at 16:52, Nick Grishin wrote:
>> 
>>> (* does not work *)
>>> func = Hold[NIntegrate[t^3, {t, x, 0}]];
>>> NMaximize[func, x]
>>> 
>>> (* works *)
>>> func = Hold[NIntegrate[t^3, {t, 0, x}]];
>>> NMinimize[func, x]
>>> 
>>> $Version
>>> 5.2 for Microsoft Windows (June 20, 2005)
>>> 
>> 
>> A bug in NMaximize? Why? It behaves exactly as it should do with this kind 
>> of input.  The problem is with MMinimize, because you when you give it 
>> nonsensical input it actually produces output, which unfortunately (by 
>> sheer accident),  looks as if it might be right. But it is nonssense 
>> nonetheless (nonsense in - > nonsense out) nonsensical, and  to convince 
>> you of it I will slightly change your input:
>> 
>> func = Hold[NIntegrate[t^3, {t, 10, x}]];
>> 
>> 
>> NMinimize[func, x]
>> 
>> 
>> {-2500.0000000000005, {x -> -0.0002833987269403981}}
>> 
>> Now, does this look like it "works"?
>> 
>> Andrzej Kozlowski
>
>
> I have to admit that my example was pointless; it does also "work" just as 
> much as your example works, although it should not. I agree that seeing this

This I understand.
n


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