Ejemplo n.º 1
0
 def loss(self, trg_batch, train):
     losses = []
     for i in range(len(trg_batch)-1):
         y = self.decode_step(trg_batch[i], train)
         loss = F.softmax_cross_entropy(y, trg_batch[i+1], 0)
         losses.append(loss)
     return F.batch.mean(F.sum(losses))
Ejemplo n.º 2
0
 def loss(self, trg_batch, train):
     """Calculates loss values."""
     losses = []
     for i in range(len(trg_batch) - 1):
         y = self.decode_step(trg_batch[i], train)
         losses.append(F.softmax_cross_entropy(y, trg_batch[i + 1], 0))
     return F.batch.mean(F.sum(losses))
Ejemplo n.º 3
0
 def loss(self, outputs, inputs):
     losses = [
         F.softmax_cross_entropy(outputs[i], inputs[i + 1], 0)
         for i in range(len(outputs))
     ]
     return F.batch.mean(F.sum(losses))
Ejemplo n.º 4
0
def main():
    # Loads data
    train_inputs = load_images("data/train-images-idx3-ubyte", NUM_TRAIN_SAMPLES)
    train_labels = load_labels("data/train-labels-idx1-ubyte", NUM_TRAIN_SAMPLES)
    test_inputs = load_images("data/t10k-images-idx3-ubyte", NUM_TEST_SAMPLES)
    test_labels = load_labels("data/t10k-labels-idx1-ubyte", NUM_TEST_SAMPLES)

    dev = D.Naive()  # or D.CUDA(gpuid)
    Device.set_default(dev)

    pw1 = Parameter([NUM_HIDDEN_UNITS, NUM_INPUT_UNITS], I.XavierUniform())
    pb1 = Parameter([NUM_HIDDEN_UNITS], I.Constant(0))
    pw2 = Parameter([NUM_OUTPUT_UNITS, NUM_HIDDEN_UNITS], I.XavierUniform())
    pb2 = Parameter([NUM_OUTPUT_UNITS], I.Constant(0))

    optimizer = O.SGD(.5)
    optimizer.add(pw1, pb1, pw2, pb2)

    def make_graph(inputs, train):
        x = F.input(inputs)

        w1 = F.parameter(pw1)
        b1 = F.parameter(pb1)
        h = F.relu(w1 @ x + b1)

        h = F.dropout(h, .5, train)

        w2 = F.parameter(pw2)
        b2 = F.parameter(pb2)
        return w2 @ h + b2

    ids = list(range(NUM_TRAIN_SAMPLES))

    g = Graph()
    Graph.set_default(g)

    for epoch in range(MAX_EPOCH):
        random.shuffle(ids)

        # Training loop
        for batch in range(NUM_TRAIN_BATCHES):
            print("\rTraining... %d / %d" % (batch + 1, NUM_TRAIN_BATCHES), end="")
            inputs = [train_inputs[ids[batch * BATCH_SIZE + i]] for i in range(BATCH_SIZE)]
            labels = [train_labels[ids[batch * BATCH_SIZE + i]] for i in range(BATCH_SIZE)]

            g.clear()

            y = make_graph(inputs, True)
            loss = F.softmax_cross_entropy(y, labels, 0)
            avg_loss = F.batch.mean(loss)

            optimizer.reset_gradients()
            avg_loss.backward()
            optimizer.update()

        print()

        match = 0

        # Test loop
        for batch in range(NUM_TEST_BATCHES):
            print("\rTesting... %d / %d" % (batch + 1, NUM_TEST_BATCHES), end="")
            inputs = [test_inputs[batch * BATCH_SIZE + i] for i in range(BATCH_SIZE)]

            g.clear()

            y = make_graph(inputs, False)
            y_val = y.to_list()
            for i in range(BATCH_SIZE):
                maxval = -1e10
                argmax = -1
                for j in range(NUM_OUTPUT_UNITS):
                    v = y_val[j + i * NUM_OUTPUT_UNITS]
                    if (v > maxval):
                        maxval = v
                        argmax = j
                if argmax == test_labels[i + batch * BATCH_SIZE]:
                    match += 1

        accuracy = 100.0 * match / NUM_TEST_SAMPLES
        print("\nepoch %d: accuracy: %.2f%%\n" % (epoch, accuracy))
Ejemplo n.º 5
0
def main():
    # Loads data
    train_inputs = load_images("data/train-images-idx3-ubyte",
                               NUM_TRAIN_SAMPLES)
    train_labels = load_labels("data/train-labels-idx1-ubyte",
                               NUM_TRAIN_SAMPLES)
    test_inputs = load_images("data/t10k-images-idx3-ubyte", NUM_TEST_SAMPLES)
    test_labels = load_labels("data/t10k-labels-idx1-ubyte", NUM_TEST_SAMPLES)

    dev = D.CUDA(0)
    Device.set_default(dev)
    g = Graph()
    Graph.set_default(g)

    # Parameters of CNNs
    # Shape: {kernel_height, kernel_width, in_channels, out_channels}
    pw_cnn1 = Parameter(Shape([KERNEL_SIZE1, KERNEL_SIZE1, 1, NUM_CHANNELS1]),
                        I.XavierUniformConv2D())
    pw_cnn2 = Parameter(
        Shape([KERNEL_SIZE2, KERNEL_SIZE2, NUM_CHANNELS1, NUM_CHANNELS2]),
        I.XavierUniformConv2D())

    # Parameters of FC layers
    pw_fc1 = Parameter(Shape([NUM_HIDDEN_UNITS, NUM_INPUT_UNITS]),
                       I.XavierUniform())
    pw_fc2 = Parameter(Shape([NUM_OUTPUT_UNITS, NUM_HIDDEN_UNITS]),
                       I.XavierUniform())
    pb_fc1 = Parameter(Shape([NUM_HIDDEN_UNITS]), I.Constant(0))
    pb_fc2 = Parameter(Shape([NUM_OUTPUT_UNITS]), I.Constant(0))

    # Optimizer
    optimizer = O.SGD(.1)
    optimizer.add(pw_cnn1, pw_cnn2, pw_fc1, pw_fc2, pb_fc1, pb_fc2)

    # Helper lambda to construct the predictor network.
    def make_graph(inputs, train):
        # Input and parameters.
        #x = F.input(Shape([IMAGE_HEIGHT, IMAGE_WIDTH], BATCH_SIZE), inputs)
        x = F.input(inputs)
        w_cnn1 = F.parameter(pw_cnn1)
        w_cnn2 = F.parameter(pw_cnn2)
        w_fc1 = F.parameter(pw_fc1)
        w_fc2 = F.parameter(pw_fc2)
        b_fc1 = F.parameter(pb_fc1)
        b_fc2 = F.parameter(pb_fc2)
        # CNNs
        h_cnn1 = F.relu(F.conv2d(x, w_cnn1, PADDING1, PADDING1, 1, 1, 1, 1))
        h_pool1 = F.max_pool2d(h_cnn1, 2, 2, 0, 0, 2, 2)
        h_cnn2 = F.relu(
            F.conv2d(h_pool1, w_cnn2, PADDING2, PADDING2, 1, 1, 1, 1))
        h_pool2 = F.max_pool2d(h_cnn2, 2, 2, 0, 0, 2, 2)
        # FC layers
        x_fc = F.dropout(F.flatten(h_pool2), .5, train)
        h_fc = F.dropout(F.relu(F.matmul(w_fc1, x_fc) + b_fc1), .5, train)
        return F.matmul(w_fc2, h_fc) + b_fc2

    # Batch randomizer
    ids = list(range(NUM_TRAIN_SAMPLES))

    for epoch in range(MAX_EPOCH):
        # Shuffles sample IDs.
        random.shuffle(ids)

        # Training loop
        for batch in range(NUM_TRAIN_BATCHES):
            print("\rTraining... %d / %d" % (batch + 1, NUM_TRAIN_BATCHES),
                  end="")
            # Makes a minibatch for training.
            inputs = [
                train_inputs[ids[batch * BATCH_SIZE + i]]
                for i in range(BATCH_SIZE)
            ]
            labels = [
                train_labels[ids[batch * BATCH_SIZE + i]]
                for i in range(BATCH_SIZE)
            ]

            # Constructs the graph.
            g.clear()
            y = make_graph(inputs, True)
            loss = F.softmax_cross_entropy(y, labels, 0)
            avg_loss = F.batch.mean(loss)

            # Dump computation graph at the first time.
            # if epoch == 0 and batch == 0:
            #     print(g.dump("dot"))

            # Implicit forward, backward, and updates parameters.
            optimizer.reset_gradients()
            avg_loss.backward()
            optimizer.update()

        print()

        match = 0

        # Test loop
        for batch in range(NUM_TEST_BATCHES):
            print("\rTesting... %d / %d" % (batch + 1, NUM_TEST_BATCHES),
                  end="")
            # Makes a test minibatch.
            inputs = [
                test_inputs[batch * BATCH_SIZE + i] for i in range(BATCH_SIZE)
            ]

            # Constructs the graph.
            g.clear()
            y = make_graph(inputs, False)

            # Gets outputs, argmax, and compares them with the label.
            y_val = y.to_list()
            for i in range(BATCH_SIZE):
                maxval = -1e10
                argmax = -1
                for j in range(NUM_OUTPUT_UNITS):
                    v = y_val[j + i * NUM_OUTPUT_UNITS]
                    if v > maxval:
                        maxval = v
                        argmax = j

                if argmax == test_labels[i + batch * BATCH_SIZE]:
                    match += 1

        accuracy = 100.0 * match / NUM_TEST_SAMPLES
        print("epoch %d: accuracy: %.2f%%" % (epoch, accuracy))

    return 0
Ejemplo n.º 6
0
def main():
    # Loads data
    train_inputs = load_images("data/train-images-idx3-ubyte",
                               NUM_TRAIN_SAMPLES)
    train_labels = load_labels("data/train-labels-idx1-ubyte",
                               NUM_TRAIN_SAMPLES)
    test_inputs = load_images("data/t10k-images-idx3-ubyte", NUM_TEST_SAMPLES)
    test_labels = load_labels("data/t10k-labels-idx1-ubyte", NUM_TEST_SAMPLES)

    # Initializes 2 device objects which manage different GPUs.
    dev0 = D.CUDA(0)
    dev1 = D.CUDA(1)

    # Parameters on GPU 0.
    pw1 = Parameter([NUM_HIDDEN_UNITS, NUM_INPUT_UNITS], I.XavierUniform(),
                    dev0)
    pb1 = Parameter([NUM_HIDDEN_UNITS], I.Constant(0), dev0)

    # Parameters on GPU 1.
    pw2 = Parameter([NUM_OUTPUT_UNITS, NUM_HIDDEN_UNITS], I.XavierUniform(),
                    dev1)
    pb2 = Parameter([NUM_OUTPUT_UNITS], I.Constant(0), dev1)

    optimizer = O.SGD(.1)
    optimizer.add(pw1, pb1, pw2, pb2)

    def make_graph(inputs):
        # We first store input values explicitly on GPU 0.
        x = F.input(inputs, device=dev0)
        w1 = F.parameter(pw1)
        b1 = F.parameter(pb1)
        w2 = F.parameter(pw2)
        b2 = F.parameter(pb2)
        # The hidden layer is calculated and implicitly stored on GPU 0.
        h_on_gpu0 = F.relu(w1 @ x + b1)
        # `copy()` transfers the hiddne layer to GPU 1.
        h_on_gpu1 = F.copy(h_on_gpu0, dev1)
        # The output layer is calculated and implicitly stored on GPU 1.
        return w2 @ h_on_gpu1 + b2

    ids = list(range(NUM_TRAIN_SAMPLES))

    g = Graph()
    Graph.set_default(g)

    for epoch in range(MAX_EPOCH):
        random.shuffle(ids)

        # Training loop
        for batch in range(NUM_TRAIN_BATCHES):
            print("\rTraining... %d / %d" % (batch + 1, NUM_TRAIN_BATCHES),
                  end="")
            inputs = [
                train_inputs[ids[batch * BATCH_SIZE + i]]
                for i in range(BATCH_SIZE)
            ]
            labels = [
                train_labels[ids[batch * BATCH_SIZE + i]]
                for i in range(BATCH_SIZE)
            ]

            g.clear()

            y = make_graph(inputs)
            loss = F.softmax_cross_entropy(y, labels, 0)
            avg_loss = F.batch.mean(loss)

            optimizer.reset_gradients()
            avg_loss.backward()
            optimizer.update()

        print()

        match = 0

        # Test loop
        for batch in range(NUM_TEST_BATCHES):
            print("\rTesting... %d / %d" % (batch + 1, NUM_TEST_BATCHES),
                  end="")
            inputs = [
                test_inputs[batch * BATCH_SIZE + i] for i in range(BATCH_SIZE)
            ]

            g.clear()

            y = make_graph(inputs)
            y_val = y.to_list()
            for i in range(BATCH_SIZE):
                maxval = -1e10
                argmax = -1
                for j in range(NUM_OUTPUT_UNITS):
                    v = y_val[j + i * NUM_OUTPUT_UNITS]
                    if (v > maxval):
                        maxval = v
                        argmax = j
                if argmax == test_labels[i + batch * BATCH_SIZE]:
                    match += 1

        accuracy = 100.0 * match / NUM_TEST_SAMPLES
        print("\nepoch %d: accuracy: %.2f%%\n" % (epoch, accuracy))