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Using Integral of an independent variable in loss function.
http://forum.alglib.net/viewtopic.php?f=2&t=3819
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Author:  Nevalyashka [ Mon Oct 09, 2017 7:25 pm ]
Post subject:  Using Integral of an independent variable in loss function.

Hello, everyone! I have one problem. There is integral of independent argument t in my loss function. I use autogk for integration and mincg subpackage for optimization. I understand that integral will be function of b and c. How can I implement the transmission of function from autogk to mincg? There is function underneath:

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Author:  Sergey.Bochkanov [ Tue Oct 10, 2017 8:31 am ]
Post subject:  Re: Using Integral of an independent variable in loss functi

It is better to calculate integral analytically and to substitute analytic expression into target function for mincg optimizer. It is integral of polynomial w.r.t. to t variable, after all.

You can implement integration via autogk in the target function, if you want, but such scheme is potentially unstable - numerical integral is always calculated with some error, and this error can confuse optimizer.

Author:  Nevalyashka [ Tue Oct 10, 2017 2:03 pm ]
Post subject:  Re: Using Integral of an independent variable in loss functi

Thank's a lot. I'll take second option, but later I realize first)

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