### Vectorized Sigmoid Activation
The sigmoid function maps any real scalar into the interval $(0, 1)$ representing probability:
$$\sigma(z) = \frac{1}{1 + e^{-z}}$$

example.pyPython 3.11

import math
def sigmoid(z):
    return 1 / (1 + math.exp(-z))
print(round(sigmoid(0), 2)) # 0.5

Python 3.11

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Interactive Challenge

+70 XP

Challenge Objective

Evaluate sigmoid at z=0 and print 'SIGMOID_ZERO: 0.5'.

solution.py

UTF-84 SpacesAuto-saved

cpython3.11:~/workspace

CPython 3.11.8 (WASM)

$python3 -u solution.py

Click "Compile & Run" (or press Ctrl + Enter) to compile AST, verify bytecode, and execute the solution.

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Module 1: Deep Neural Network Foundations & Backprop•Lesson 1

1.1 Vectorized Logistic Regression for Binary Classification