Attribute VB_Name = "basFormulae"
Public Function sigmoid(x As Single) As Single  'activation function, pg 293 for bipolar, f(x)
  sigmoid = (2 / (1 + Exp(-x))) - 1
End Function

Public Function revSigmoid(x As Single) As Single ' f'(x)
    revSigmoid = (0.5 * (1 + sigmoid(x)) * (1 - sigmoid(x)))
End Function