Re^2: AI::NNFlex::Backprop error not decreasing

in reply to Re: AI::NNFlex::Backprop error not decreasing
in thread AI::NNFlex::Backprop error not decreasing

If my memory hasn't too much rust, the derivative you're looking for is:

exp(-$value) * ((1 + exp(-$value)) ** -2)

Flavio.

-- Don't fool yourself.

Comment on Re^2: AI::NNFlex::Backprop error not decreasing

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Re^3: AI::NNFlex::Backprop error not decreasing by g0n (Priest) on Mar 21, 2005 at 12:46 UTC
Thanks frodo72, that seems to do the job. I'll put that in the code for the next release, although I'd still recommend the OP uses tanh, as it seems to be more effective with this implementation of backprop. g0n, backpropagated monk	[reply]
Re^3: AI::NNFlex::Backprop error not decreasing by caedes (Pilgrim) on Mar 21, 2005 at 19:51 UTC
Just a slight correction to frodo72's derivative: `-1 * exp(-$value) * ((1 + exp(-$value)) ** -2)` [download] Update: nevermind, forgot a negative that canceled. =\ -caedes	[reply] [d/l]

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