Exemplo n.º 1
0
    def __init__(self, n_in, n_out, block_size, activation, do_dropout=False,
                 reinforce_params="reinforce",
                 default_params="default"):
        self.block_size = block_size
        self.nblocks = n_out / block_size
        self.do_dropout = do_dropout
        assert n_out % block_size == 0

        self.h = HiddenLayer(n_in, n_out, activation)
        shared.bind(reinforce_params)
        self.d = HiddenLayer(n_in, self.nblocks, T.nnet.sigmoid)
        shared.bind(default_params)
Exemplo n.º 2
0
    def __init__(self,
                 n_in,
                 n_out,
                 block_size,
                 activation,
                 rate,
                 do_dropout=False):
        self.rate = rate
        self.block_size = block_size
        self.nblocks = n_out / block_size
        self.do_dropout = do_dropout
        assert n_out % block_size == 0

        self.h = HiddenLayer(n_in, n_out, activation)
Exemplo n.º 3
0
def build_model(new_model=True):
    momentum_epsilon = 0.9

    nhidden = [64, 64]
    L2reg = 0.001

    vanilla = True

    hyperparams = locals()

    if new_model:
        expid = str(uuid.uuid4())
        import os
        import os.path
        code = file(os.path.abspath(__file__), 'r').read()
        os.mkdir(expid)
        os.chdir(expid)
        file('code.py', 'w').write(code)

        print expid

        f = file("params.txt", 'w')
        for i in hyperparams:
            f.write("%s:%s\n" % (i, str(hyperparams[i])))
        f.close()

    params = []
    shared.bind(params)

    rect = lambda x: T.maximum(0, x)
    act = T.tanh

    model = StackModel([
        HiddenLayer(32 * 32 * 3, nhidden[0], act),
        Dropout(),
        HiddenLayer(nhidden[0], nhidden[1], act),
        Dropout(),
        HiddenLayer(nhidden[-1], 10, T.nnet.softmax)
    ])

    x = T.matrix()
    y = T.ivector()
    lr = T.scalar()

    y_hat, = model(x)
    loss = T.nnet.categorical_crossentropy(y_hat, y)
    cost = T.sum(loss)
    l2 = lambda x: sum([T.sum(i**2) for i in x])
    updates = []
    error = T.sum(T.neq(y_hat.argmax(axis=1), y))
    nn_regularization = L2reg * l2(params)

    grads = T.grad(cost + nn_regularization, params)
    updates += gradient_descent(params, grads, lr)

    learn = theano.function([x, y, lr], [cost, error],
                            updates=updates,
                            allow_input_downcast=True)
    test = theano.function([x, y], [cost, error], allow_input_downcast=True)

    return model, learn, test