Just a slight correction to frodo72's derivative: 
-1 * exp(-$value) * ((1 + exp(-$value)) ** -2)

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Update: nevermind, forgot a negative that canceled. =\

-caedes

In reply to Re^3: AI::NNFlex::Backprop error not decreasing by caedes
in thread AI::NNFlex::Backprop error not decreasing by thealienz1

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