please explain to a math and python dummy. I tried both
s = 1/(1 + e^{-x})
s = math.exp(x)
The point is that math.exp(x) is the way you say e^x in python in the case that x is a scalar value. So e^{-x} would be math.exp(-x), right? Now you need to incorporate that into the formula for sigmoid. That would be:
\sigma(x) = \displaystyle \frac {1}{1 + e^{-x}}
So how would you write that in python?
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Also, I would point out that in python the ^ symbol does not mean exponentiation, for that you need to use two asterisks **, and you should use () instead of {} in arithmetic expressions.
For example, to write a^b in python you use a**b.
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1/(1+math.exp(-x)) works. You mean 1/(1+math.exp**-x)? It does not pass.
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My comment was for python in general, not for this particular case. I was only adding information because I saw you tried to use the incorrect symbol for exponentiation
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math.exp is the name of a function in python. You call (‘invoke’) a function with an argument. What would it mean to raise a function to a power? You can find the documentation for math.exp by googling “python math exp”.
BTW the operator ^ in python is “exclusive OR”, which is a Boolean operation.