Neural Networks from Scratch in Python by Harrison Kinsley, Daniel Kukie a

Chapter 2 - Coding Our First Neurons - Neural Networks from Scratch in Python
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What might we need to change if we have 4 inputs, rather than the 3 we’ve just shown? Next to
the additional input, we need to add an associated weight, which this new input will be multiplied
with. We’ll make up a value for this new weight as well. Code for this data could be:
inputs ​= ​[​1.0​, ​2.0​, ​3.0​, ​2.5​]
weights ​= ​[​0.2​, ​0.8​, ​-​0.5​, ​1.0​]
bias ​= ​2.0
Which could be depicted visually as:
Fig 2.02:​ Visualizing how the inputs, weights, and biases from the code interact with the neuron.
Anim 2.02:​ ​https://nnfs.io/djp
All together in code, including the new input and weight, to produce output:
inputs ​= ​[​1.0​, ​2.0​, ​3.0​, ​2.5​]
weights ​= ​[​0.2​, ​0.8​, ​-​0.5​, ​1.0​]
bias ​= ​2.0
output ​= ​(inputs[​0​]​*​weights[​0​] ​+
​inputs[​1​]​*​weights[​1​] ​+
​inputs[​2​]​*​weights[​2​] ​+
​inputs[​3​]​*​weights[​3​] ​+ ​bias)