Math

[Download this notebook](07 - First Neural Net.ipynb) In this lesson you’ll learn: how one-hot encoding works. how to program a simple neural net in Python. Before we train the neural network, the first thing we need to do is load the relevant libraries and functions. import numpy as np from matplotlib import pyplot as plt %matplotlib inline Activation functions def sigmoid(x): return 1 / (1 + np.exp(-x)) # np.exp() = e^() def softmax(x, axis=1): return np.

[Download this notebook](06 - Linear Algebra for NN.ipynb) In this lesson you’ll learn: about vectors and matrices and how to do simple calculations with them in Python. how to calculate the derivative of simple functions. how the chain rule works and why it is so useful for neural networks. Today we will explain the essential mathematical principles for neural networks. The first essential mathematical concept is the vector. A vector represents a point in a space that is described by several values.