# Sigmoid

## 19.11.2020 | Standard Functions/Activation

### Contents/Index

@Sigmoid

Sigmoid functions are a class of functions with an S-shaped curve. A common example is the logistic function given as $$f(x) = \frac{1}{1 + e^{-x}}$$ This function is plotted in Figure 1.

The following Python3 code has been used for the plot:

import matplotlib.pyplot as plt import math def f(x): return 1 / (1.0 + math.exp(-x)) xs = [float(x) / 100.0 for x in range(-1000,1000)] ys = [f(y) for y in xs] plt.plot(xs,ys) plt.show()

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