Example #1
0
def df(x,y,W,b):
    p = part2.forward(x, W, b)

    grad_w = np.matmul((p-y), x.T).T
    grad_b = np.sum((p-y), 1).reshape((10,1))

    return grad_w, grad_b
Example #2
0
def part5(alpha_w, alpha_b, _max_iter, printing):
    M = loadmat("mnist_all.mat")

    results_val = []
    results_train = []
    results_test = []
    x = []
    train_set, train_set_sol, val_set, val_set_sol, test_set, test_set_sol = part4.generate_sets(
        M, 5000)
    W_init = np.random.rand(784, 10)

    step = 20
    for i in range(step, _max_iter, step):
        print(i)
        W, b = grad_descent(part3.f, part3.df, train_set, train_set_sol,
                            W_init, alpha_w, alpha_b, i, 0.9, True)

        y_pred = part2.forward(val_set, W, b)
        results_val += [
            np.mean(np.argmax(y_pred, 0) == np.argmax(val_set_sol, 0))
        ]
        y_pred = part2.forward(train_set, W, b)
        results_train += [
            np.mean(np.argmax(y_pred, 0) == np.argmax(train_set_sol, 0))
        ]
        y_pred = part2.forward(test_set, W, b)
        results_test += [
            np.mean(np.argmax(y_pred, 0) == np.argmax(test_set_sol, 0))
        ]
        print results_test
        print results_train
        print results_val
        x += [i]

    pickle.dump(W, open("part4W_shichen.p", "wb"))
    plt.plot(x, results_val, 'y', label="validation set")
    plt.plot(x, results_train, 'g', label="training set")
    plt.plot(x, results_test, 'r', label="test set")
    plt.title("Part 5 Learning Curve")
    plt.ylabel("accuracy")
    plt.xlabel("iterations")
    plt.show()
Example #3
0
def test2(database, solutions, W, b):
    correct = 0
    database = database.T
    solutions = solutions.T

    for i in range(len(database)):
        guess = part2.forward(database[i], W, b)
        if np.argmax(guess) == np.argmax(solutions[i]):
            correct += 1

    return correct / float(len(database))
Example #4
0
def test(database, size, W, b):
    test_set = []
    correct = 0

    for i in range(size):
        rand_dgt = np.random.random_integers(0, 9)
        test_set += [database["test" + str(rand_dgt)][i]]
        guess = part2.forward(test_set[i], W, b)
        if guess == rand_dgt:
            correct += 1

    return correct / size
Example #5
0
def f(x, W, b, y):
    p = part2.forward(x,W,b)
    return -sum(y*log(p)) / x.shape[1]