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

44 lines
1.2 KiB
Matlab

function p = predict(Theta1, Theta2, X)
%PREDICT Predict the label of an input given a trained neural network
% p = PREDICT(Theta1, Theta2, X) 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);
% You need to return the following variables correctly
p = zeros(size(X, 1), 1);
% ====================== YOUR CODE HERE ======================
% Instructions: Complete the following code to make predictions using
% your learned neural network. You should set p to a
% vector containing labels between 1 to num_labels.
%
% Hint: The max function might come in useful. In particular, the max
% function can also return the index of the max element, for more
% information see 'help max'. If your examples are in rows, then, you
% can use max(A, [], 2) to obtain the max for each row.
%
X = [ones(rows(X), 1) X];
z2 = (Theta1*X')';
a2 = sigmoid(z2);
a2 = [ones(rows(a2), 1) a2];
z3 = Theta2*a2';
a3 = sigmoid(z3);
a3 = a3';
[max, imax] = max(a3, [], 2);
p = imax;
% =========================================================================
end