Week 4

Prediction using Neural Networks.

Finishes Week 4!

W4/machine-learning-ex3/ex3/ex3.m

@@ -39,10 +39,10 @@ m = size(X, 1);
 rand_indices = randperm(m);
 sel = X(rand_indices(1:100), :);
 
-%displayData(sel);
+displayData(sel);
 
 fprintf('Program paused. Press enter to continue.\n');
-%pause;
+pause;
 
 %% ============ Part 2: Vectorize Logistic Regression ============
 %  In this part of the exercise, you will reuse your logistic regression

W4/machine-learning-ex3/ex3/predict.m

@@ -10,6 +10,9 @@ num_labels = size(Theta2, 1);
 % You need to return the following variables correctly 
 p = zeros(size(X, 1), 1);
 
+% Add ones to the X data matrix
+X = [ones(m, 1) X];
+
 % ====================== YOUR CODE HERE ======================
 % Instructions: Complete the following code to make predictions using
 %               your learned neural network. You should set p to a 
@@ -21,15 +24,11 @@ p = zeros(size(X, 1), 1);
 %       can use max(A, [], 2) to obtain the max for each row.
 %
 
+a2 = sigmoid(X * Theta1');
+a2 = [ones(m, 1) a2];
+a3 = sigmoid(a2 * Theta2');
 
-
-
-
-
-
-
-
+[val, p] = max(a3, [], 2);
 % =========================================================================
 
-
 end