Neural Networks
Outline
Neural Networks: Introduction and Forward Propagation
Neutral Networks: Back Propagation
Neutral Networks: Classifying Hand Written Digits
Neural Networks: Batching
Classifying Hand Written Digits Using Keras
Videos
Exclusive OR (XOR)
Hidden node/layer
Python functions
Matrix multiply and matrix shapes
Hidden error
One hot encoding
MNIST data set
List slicing/indexing
Batching
Batch size
Use
from tensorflow.keras.utils import to_categorical
from tensorflow.keras import optimizers
Ideas for further coding projects
Make a plot of the loss function as a function of epochs
Use the weights you find with mnist_train_small.csv to make predictions for mnist_test.csv. Is the accuracy better or worse? Why?
Write a digit on a piece of paper and take a photo. Use Photutils.com to crop and resize to 28x28 pixels and upload to Google Colab. Use img = cv2.imread('image.jpg',0) to convert the image to a numpy array and see if your neural network can recognise it (remember to reshape it!).