Update NNpredict.m

NNpredict.m

@@ -1,17 +1,16 @@
 function p = NNpredict(Theta1, Theta2, X)
 
+    %  This function outputs the predicted label of X given the trained weights
+    %  of a neural network (Theta1, Theta2).
+
     % Useful values
     m = size(X, 1);
     num_labels = size(Theta2, 1);
-    p = zeros(size(X, 1), 1);
 
-    % Add ones to the X data matrix
-    X = [ones(m, 1) X];
+    p = zeros(size(X, 1), 1);
 
-    newX = sigmoid(X*Theta1');
-    newX = [ones(m, 1) newX];
-    p = sigmoid(newX*Theta2');
-    [maxP, indP] = max(p, [], 2);
-    p = indP;
+    h1 = sigmoid([ones(m, 1) X] * Theta1');
+    h2 = sigmoid([ones(m, 1) h1] * Theta2');
+    [dummy, p] = max(h2, [], 2);
 
 end