def model(n_inputs, n_outputs):
        clf = NeuralNetwork(optimizer=Adam(), loss=SquareLoss)
        clf.add(Dense(64, input_shape=(n_inputs, )))
        clf.add(Activation('relu'))
        clf.add(Dense(n_outputs))

        return clf
Beispiel #2
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    def __init__(self):
        self.img_rows = 28
        self.img_cols = 28
        self.channels = 1
        self.img_shape = (self.channels, self.img_rows, self.img_cols)

        optimizer = Adam(learning_rate=0.0002, b1=0.5)
        loss_function = CrossEntropy

        # Build the discriminator
        self.discriminator = self.build_discriminator(optimizer, loss_function)

        # Build the generator
        self.generator = self.build_generator(optimizer, loss_function)

        # Build the combined model
        self.combined = NeuralNetwork(optimizer=optimizer, loss=loss_function)
        self.combined.layers += self.generator.layers[:]
        self.combined.layers += self.discriminator.layers[:]
Beispiel #3
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    def __init__(self):
        self.img_rows = 28
        self.img_cols = 28
        self.img_dim = self.img_rows * self.img_cols
        self.latent_dim = 100

        optimizer = Adam(learning_rate=0.0002, b1=0.5)
        loss_function = CrossEntropy

        # Build the discriminator
        self.discriminator = self.build_discriminator(optimizer, loss_function)

        # Build the generator
        self.generator = self.build_generator(optimizer, loss_function)

        # Build the combined model
        self.combined = NeuralNetwork(optimizer=optimizer, loss=loss_function)
        self.combined.layers += self.generator.layers[:]
        self.combined.layers += self.discriminator.layers[:]

        print()
        self.generator.summary(name="Generator")
        self.discriminator.summary(name="Discriminator")
    def __init__(self):
        self.img_rows = 28 
        self.img_cols = 28
        self.channels = 1
        self.img_shape = (self.channels, self.img_rows, self.img_cols)

        optimizer = Adam(learning_rate=0.0002, b1=0.5)
        loss_function = CrossEntropy

        # Build the discriminator
        self.discriminator = self.build_discriminator(optimizer, loss_function)

        # Build the generator
        self.generator = self.build_generator(optimizer, loss_function)

        # Build the combined model
        self.combined = NeuralNetwork(optimizer=optimizer, loss=loss_function)
        self.combined.layers += self.generator.layers[:]
        self.combined.layers += self.discriminator.layers[:]
Beispiel #5
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    def build_discriminator(self, optimizer, loss_function):

        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(
            Conv2D(32,
                   filter_shape=(3, 3),
                   stride=2,
                   input_shape=self.img_shape,
                   padding='same'))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.25))
        model.add(Conv2D(64, filter_shape=(3, 3), stride=2, padding='same'))
        model.add(ZeroPadding2D(padding=((0, 1), (0, 1))))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.25))
        model.add(Conv2D(128, filter_shape=(3, 3), stride=2, padding='same'))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.25))
        model.add(Conv2D(256, filter_shape=(3, 3), stride=1, padding='same'))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.25))
        model.add(Flatten())
        model.add(Dense(128))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(2))
        model.add(Activation('softmax'))

        return model
Beispiel #6
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    def build_generator(self, optimizer, loss_function):

        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Dense(128 * 7 * 7, input_shape=(100, )))
        model.add(Activation('leaky_relu'))
        model.add(Reshape((128, 7, 7)))
        model.add(UpSampling2D())
        model.add(Conv2D(128, filter_shape=(3, 3), padding='same'))
        model.add(Activation("leaky_relu"))
        model.add(UpSampling2D())
        model.add(Conv2D(64, filter_shape=(3, 3), padding='same'))
        model.add(Activation("leaky_relu"))
        model.add(Conv2D(1, filter_shape=(3, 3), padding='same'))
        model.add(Activation("tanh"))

        return model
Beispiel #7
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class DCGAN():
    def __init__(self):
        self.img_rows = 28
        self.img_cols = 28
        self.channels = 1
        self.img_shape = (self.channels, self.img_rows, self.img_cols)

        optimizer = Adam(learning_rate=0.0002, b1=0.5)
        loss_function = CrossEntropy

        # Build the discriminator
        self.discriminator = self.build_discriminator(optimizer, loss_function)

        # Build the generator
        self.generator = self.build_generator(optimizer, loss_function)

        # Build the combined model
        self.combined = NeuralNetwork(optimizer=optimizer, loss=loss_function)
        self.combined.layers += self.generator.layers[:]
        self.combined.layers += self.discriminator.layers[:]

    def build_generator(self, optimizer, loss_function):

        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Dense(128 * 7 * 7, input_shape=(100, )))
        model.add(Activation('leaky_relu'))
        model.add(Reshape((128, 7, 7)))
        model.add(UpSampling2D())
        model.add(Conv2D(128, filter_shape=(3, 3), padding='same'))
        model.add(Activation("leaky_relu"))
        model.add(UpSampling2D())
        model.add(Conv2D(64, filter_shape=(3, 3), padding='same'))
        model.add(Activation("leaky_relu"))
        model.add(Conv2D(1, filter_shape=(3, 3), padding='same'))
        model.add(Activation("tanh"))

        return model

    def build_discriminator(self, optimizer, loss_function):

        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(
            Conv2D(32,
                   filter_shape=(3, 3),
                   stride=2,
                   input_shape=self.img_shape,
                   padding='same'))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.25))
        model.add(Conv2D(64, filter_shape=(3, 3), stride=2, padding='same'))
        model.add(ZeroPadding2D(padding=((0, 1), (0, 1))))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.25))
        model.add(Conv2D(128, filter_shape=(3, 3), stride=2, padding='same'))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.25))
        model.add(Conv2D(256, filter_shape=(3, 3), stride=1, padding='same'))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.25))
        model.add(Flatten())
        model.add(Dense(128))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(2))
        model.add(Activation('softmax'))

        return model

    def train(self, epochs, batch_size=128, save_interval=50):

        mnist = fetch_mldata('MNIST original')

        X = mnist.data.reshape((-1, ) + self.img_shape)
        y = mnist.target

        # Rescale -1 to 1
        X = (X.astype(np.float32) - 127.5) / 127.5

        half_batch = int(batch_size / 2)

        for epoch in range(epochs):

            # ---------------------
            #  Train Discriminator
            # ---------------------

            self.discriminator.set_trainable(True)

            # Select a random half batch of images
            idx = np.random.randint(0, X.shape[0], half_batch)
            imgs = X[idx]

            noise = np.random.normal(0, 1, (half_batch, 100))

            # Generate a half batch of images
            gen_imgs = self.generator.predict(noise)

            valid = np.concatenate((np.ones(
                (half_batch, 1)), np.zeros((half_batch, 1))),
                                   axis=1)
            fake = np.concatenate((np.zeros(
                (half_batch, 1)), np.ones((half_batch, 1))),
                                  axis=1)

            # Train the discriminator
            d_loss_real, d_acc_real = self.discriminator.train_on_batch(
                imgs, valid)
            d_loss_fake, d_acc_fake = self.discriminator.train_on_batch(
                gen_imgs, fake)
            d_loss = 0.5 * (d_loss_real + d_loss_fake)
            d_acc = 0.5 * (d_acc_real + d_acc_fake)

            # ---------------------
            #  Train Generator
            # ---------------------

            # We only want to train the generator for the combined model
            self.discriminator.set_trainable(False)

            # Sample noise and use as generator input
            noise = np.random.normal(0, 1, (batch_size, 100))

            # The generator wants the discriminator to label the generated samples as valid
            valid = np.concatenate((np.ones(
                (batch_size, 1)), np.zeros((batch_size, 1))),
                                   axis=1)

            # Train the generator
            g_loss, g_acc = self.combined.train_on_batch(noise, valid)

            # Display the progress
            print("%d [D loss: %f, acc: %.2f%%] [G loss: %f, acc: %.2f%%]" %
                  (epoch, d_loss, 100 * d_acc, g_loss, 100 * g_acc))

            # If at save interval => save generated image samples
            if epoch % save_interval == 0:
                self.save_imgs(epoch)

    def save_imgs(self, epoch):
        r, c = 5, 5
        noise = np.random.normal(0, 1, (r * c, 100))
        gen_imgs = self.generator.predict(noise)

        # Rescale images 0 - 1
        gen_imgs = 0.5 * gen_imgs + 0.5

        fig, axs = plt.subplots(r, c)
        plt.suptitle("Generative Adversarial Network")
        cnt = 0
        for i in range(r):
            for j in range(c):
                axs[i, j].imshow(gen_imgs[cnt, 0, :, :], cmap='gray')
                axs[i, j].axis('off')
                cnt += 1
        fig.savefig("mnist_%d.png" % epoch)
        plt.close()
Beispiel #8
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def main():

    optimizer = Adam()

    #-----
    # MLP
    #-----

    data = datasets.load_digits()
    X = data.data
    y = data.target

    # Convert to one-hot encoding
    y = to_categorical(y.astype("int"))

    n_samples = np.shape(X)
    n_hidden = 512

    X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.4, seed=1)

    clf = NeuralNetwork(optimizer=optimizer,
                        loss=CrossEntropy,
                        validation_data=(X_test, y_test))

    clf.add(Dense(n_hidden, input_shape=(8*8,)))
    clf.add(Activation('leaky_relu'))
    clf.add(Dense(n_hidden))
    clf.add(Activation('leaky_relu'))
    clf.add(Dropout(0.25))
    clf.add(Dense(n_hidden))
    clf.add(Activation('leaky_relu'))
    clf.add(Dropout(0.25))
    clf.add(Dense(n_hidden))
    clf.add(Activation('leaky_relu'))
    clf.add(Dropout(0.25))
    clf.add(Dense(10))
    clf.add(Activation('softmax'))

    print ()
    clf.summary(name="MLP")
    
    train_err, val_err = clf.fit(X_train, y_train, n_epochs=50, batch_size=256)
    
    # Training and validation error plot
    n = len(train_err)
    training, = plt.plot(range(n), train_err, label="Training Error")
    validation, = plt.plot(range(n), val_err, label="Validation Error")
    plt.legend(handles=[training, validation])
    plt.title("Error Plot")
    plt.ylabel('Error')
    plt.xlabel('Iterations')
    plt.show()

    # Predict labels of the test data
    y_pred = np.argmax(clf.predict(X_test), axis=1)
    y_test = np.argmax(y_test, axis=1)

    accuracy = accuracy_score(y_test, y_pred)
    print ("Accuracy:", accuracy)

    # Reduce dimension to 2D using PCA and plot the results
    Plot().plot_in_2d(X_test, y_pred, title="Multilayer Perceptron", accuracy=accuracy, legend_labels=range(10))
Beispiel #9
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def main():

    optimizer = Adam()

    def gen_mult_ser(nums):
        """ Method which generates multiplication series """
        X = np.zeros([nums, 10, 61], dtype=float)
        y = np.zeros([nums, 10, 61], dtype=float)
        for i in range(nums):
            start = np.random.randint(2, 7)
            mult_ser = np.linspace(start, start*10, num=10, dtype=int)
            X[i] = to_categorical(mult_ser, n_col=61)
            y[i] = np.roll(X[i], -1, axis=0)
        y[:, -1, 1] = 1 # Mark endpoint as 1
        return X, y


    def gen_num_seq(nums):
        """ Method which generates sequence of numbers """
        X = np.zeros([nums, 10, 20], dtype=float)
        y = np.zeros([nums, 10, 20], dtype=float)
        for i in range(nums):
            start = np.random.randint(0, 10)
            num_seq = np.arange(start, start+10)
            X[i] = to_categorical(num_seq, n_col=20)
            y[i] = np.roll(X[i], -1, axis=0)
        y[:, -1, 1] = 1 # Mark endpoint as 1
        return X, y

    X, y = gen_mult_ser(3000)
    X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.4)

    # Model definition
    clf = NeuralNetwork(optimizer=optimizer,
                        loss=CrossEntropy)
    clf.add(RNN(10, activation="tanh", bptt_trunc=5, input_shape=(10, 61)))
    clf.add(Activation('softmax'))
    clf.summary("RNN")

    # Print a problem instance and the correct solution
    tmp_X = np.argmax(X_train[0], axis=1)
    tmp_y = np.argmax(y_train[0], axis=1)
    print ("Number Series Problem:")
    print ("X = [" + " ".join(tmp_X.astype("str")) + "]")
    print ("y = [" + " ".join(tmp_y.astype("str")) + "]")
    print ()

    train_err, _ = clf.fit(X_train, y_train, n_epochs=500, batch_size=512)

    # Predict labels of the test data
    y_pred = np.argmax(clf.predict(X_test), axis=2)
    y_test = np.argmax(y_test, axis=2)

    print ()
    print ("Results:")
    for i in range(5):
        # Print a problem instance and the correct solution
        tmp_X = np.argmax(X_test[i], axis=1)
        tmp_y1 = y_test[i]
        tmp_y2 = y_pred[i]
        print ("X      = [" + " ".join(tmp_X.astype("str")) + "]")
        print ("y_true = [" + " ".join(tmp_y1.astype("str")) + "]")
        print ("y_pred = [" + " ".join(tmp_y2.astype("str")) + "]")
        print ()
    
    accuracy = np.mean(accuracy_score(y_test, y_pred))
    print ("Accuracy:", accuracy)

    training = plt.plot(range(500), train_err, label="Training Error")
    plt.title("Error Plot")
    plt.ylabel('Training Error')
    plt.xlabel('Iterations')
    plt.show()
    def build_discriminator(self, optimizer, loss_function):
        
        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Flatten(input_shape=self.img_shape))
        model.add(Dense(512))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(256))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(2))
        model.add(Activation('softmax'))

        return model
    def build_generator(self, optimizer, loss_function):
        
        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Dense(256, input_shape=(100,)))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(512))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(1024))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(np.prod(self.img_shape)))
        model.add(Activation('tanh'))
        model.add(Reshape(self.img_shape))

        return model
class GAN():
    def __init__(self):
        self.img_rows = 28 
        self.img_cols = 28
        self.channels = 1
        self.img_shape = (self.channels, self.img_rows, self.img_cols)

        optimizer = Adam(learning_rate=0.0002, b1=0.5)
        loss_function = CrossEntropy

        # Build the discriminator
        self.discriminator = self.build_discriminator(optimizer, loss_function)

        # Build the generator
        self.generator = self.build_generator(optimizer, loss_function)

        # Build the combined model
        self.combined = NeuralNetwork(optimizer=optimizer, loss=loss_function)
        self.combined.layers += self.generator.layers[:]
        self.combined.layers += self.discriminator.layers[:]

    def build_generator(self, optimizer, loss_function):
        
        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Dense(256, input_shape=(100,)))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(512))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(1024))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(np.prod(self.img_shape)))
        model.add(Activation('tanh'))
        model.add(Reshape(self.img_shape))

        return model

    def build_discriminator(self, optimizer, loss_function):
        
        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Flatten(input_shape=self.img_shape))
        model.add(Dense(512))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(256))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(2))
        model.add(Activation('softmax'))

        return model


    def train(self, epochs, batch_size=128, save_interval=50):

        mnist = fetch_mldata('MNIST original')

        X = mnist.data.reshape((-1,) + self.img_shape)
        y = mnist.target

        # Rescale -1 to 1
        X = (X.astype(np.float32) - 127.5) / 127.5

        half_batch = int(batch_size / 2)

        for epoch in range(epochs):

            # ---------------------
            #  Train Discriminator
            # ---------------------

            self.discriminator.set_trainable(True)

            # Select a random half batch of images
            idx = np.random.randint(0, X.shape[0], half_batch)
            imgs = X[idx]

            noise = np.random.normal(0, 1, (half_batch, 100))

            # Generate a half batch of images
            gen_imgs = self.generator.predict(noise)

            valid = np.concatenate((np.ones((half_batch, 1)), np.zeros((half_batch, 1))), axis=1)
            fake = np.concatenate((np.zeros((half_batch, 1)), np.ones((half_batch, 1))), axis=1)

            # Train the discriminator
            d_loss_real, d_acc_real = self.discriminator.train_on_batch(imgs, valid)
            d_loss_fake, d_acc_fake = self.discriminator.train_on_batch(gen_imgs, fake)
            d_loss = 0.5 * (d_loss_real + d_loss_fake)
            d_acc = 0.5 * (d_acc_real + d_acc_fake)


            # ---------------------
            #  Train Generator
            # ---------------------

            # We only want to train the generator for the combined model
            self.discriminator.set_trainable(False)

            # Sample noise and use as generator input
            noise = np.random.normal(0, 1, (batch_size, 100))

            # The generator wants the discriminator to label the generated samples as valid
            valid = np.concatenate((np.ones((batch_size, 1)), np.zeros((batch_size, 1))), axis=1)

            # Train the generator
            g_loss, g_acc = self.combined.train_on_batch(noise, valid)

            # Display the progress
            print ("%d [D loss: %f, acc: %.2f%%] [G loss: %f, acc: %.2f%%]" % (epoch, d_loss, 100*d_acc, g_loss, 100*g_acc))

            # If at save interval => save generated image samples
            if epoch % save_interval == 0:
                self.save_imgs(epoch)

    def save_imgs(self, epoch):
        r, c = 5, 5
        noise = np.random.normal(0, 1, (r * c, 100))
        gen_imgs = self.generator.predict(noise)

        # Rescale images 0 - 1
        gen_imgs = 0.5 * gen_imgs + 0.5

        fig, axs = plt.subplots(r, c)
        plt.suptitle("Generative Adversarial Network")
        cnt = 0
        for i in range(r):
            for j in range(c):
                axs[i,j].imshow(gen_imgs[cnt,0,:,:], cmap='gray')
                axs[i,j].axis('off')
                cnt += 1
        fig.savefig("mnist_%d.png" % epoch)
        plt.close()
    def build_discriminator(self, optimizer, loss_function):

        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Flatten(input_shape=self.img_shape))
        model.add(Dense(512))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(256))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(2))
        model.add(Activation('softmax'))

        return model
    def build_generator(self, optimizer, loss_function):

        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Dense(256, input_shape=(100, )))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(512))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(1024))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(np.prod(self.img_shape)))
        model.add(Activation('tanh'))
        model.add(Reshape(self.img_shape))

        return model
Beispiel #15
0
class GAN():
    """A Generative Adversarial Network with deep fully-connected neural nets as
    Generator and Discriminator.

    Training Data: MNIST Handwritten Digits (28x28 images)
    """
    def __init__(self):
        self.img_rows = 28
        self.img_cols = 28
        self.img_dim = self.img_rows * self.img_cols
        self.latent_dim = 100

        optimizer = Adam(learning_rate=0.0002, b1=0.5)
        loss_function = CrossEntropy

        # Build the discriminator
        self.discriminator = self.build_discriminator(optimizer, loss_function)

        # Build the generator
        self.generator = self.build_generator(optimizer, loss_function)

        # Build the combined model
        self.combined = NeuralNetwork(optimizer=optimizer, loss=loss_function)
        self.combined.layers += self.generator.layers[:]
        self.combined.layers += self.discriminator.layers[:]

        print()
        self.generator.summary(name="Generator")
        self.discriminator.summary(name="Discriminator")

    def build_generator(self, optimizer, loss_function):

        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Dense(256, input_shape=(self.latent_dim, )))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(512))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(1024))
        model.add(Activation('leaky_relu'))
        model.add(BatchNormalization(momentum=0.8))
        model.add(Dense(self.img_dim))
        model.add(Activation('tanh'))

        return model

    def build_discriminator(self, optimizer, loss_function):

        model = NeuralNetwork(optimizer=optimizer, loss=loss_function)

        model.add(Dense(512, input_shape=(self.img_dim, )))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(256))
        model.add(Activation('leaky_relu'))
        model.add(Dropout(0.5))
        model.add(Dense(2))
        model.add(Activation('softmax'))

        return model

    def train(self, n_epochs, batch_size=128, save_interval=50):

        mnist = fetch_mldata('MNIST original')

        X = mnist.data
        y = mnist.target

        # Rescale [-1, 1]
        X = (X.astype(np.float32) - 127.5) / 127.5

        half_batch = int(batch_size / 2)

        for epoch in range(n_epochs):

            # ---------------------
            #  Train Discriminator
            # ---------------------

            self.discriminator.set_trainable(True)

            # Select a random half batch of images
            idx = np.random.randint(0, X.shape[0], half_batch)
            imgs = X[idx]

            # Sample noise to use as generator input
            noise = np.random.normal(0, 1, (half_batch, self.latent_dim))

            # Generate a half batch of images
            gen_imgs = self.generator.predict(noise)

            # Valid = [1, 0], Fake = [0, 1]
            valid = np.concatenate((np.ones(
                (half_batch, 1)), np.zeros((half_batch, 1))),
                                   axis=1)
            fake = np.concatenate((np.zeros(
                (half_batch, 1)), np.ones((half_batch, 1))),
                                  axis=1)

            # Train the discriminator
            d_loss_real, d_acc_real = self.discriminator.train_on_batch(
                imgs, valid)
            d_loss_fake, d_acc_fake = self.discriminator.train_on_batch(
                gen_imgs, fake)
            d_loss = 0.5 * (d_loss_real + d_loss_fake)
            d_acc = 0.5 * (d_acc_real + d_acc_fake)

            # ---------------------
            #  Train Generator
            # ---------------------

            # We only want to train the generator for the combined model
            self.discriminator.set_trainable(False)

            # Sample noise and use as generator input
            noise = np.random.normal(0, 1, (batch_size, self.latent_dim))

            # The generator wants the discriminator to label the generated samples as valid
            valid = np.concatenate((np.ones(
                (batch_size, 1)), np.zeros((batch_size, 1))),
                                   axis=1)

            # Train the generator
            g_loss, g_acc = self.combined.train_on_batch(noise, valid)

            # Display the progress
            print("%d [D loss: %f, acc: %.2f%%] [G loss: %f, acc: %.2f%%]" %
                  (epoch, d_loss, 100 * d_acc, g_loss, 100 * g_acc))

            # If at save interval => save generated image samples
            if epoch % save_interval == 0:
                self.save_imgs(epoch)

    def save_imgs(self, epoch):
        r, c = 5, 5  # Grid size
        noise = np.random.normal(0, 1, (r * c, self.latent_dim))
        # Generate images and reshape to image shape
        gen_imgs = self.generator.predict(noise).reshape(
            (-1, self.img_rows, self.img_cols))

        # Rescale images 0 - 1
        gen_imgs = 0.5 * gen_imgs + 0.5

        fig, axs = plt.subplots(r, c)
        plt.suptitle("Generative Adversarial Network")
        cnt = 0
        for i in range(r):
            for j in range(c):
                axs[i, j].imshow(gen_imgs[cnt, :, :], cmap='gray')
                axs[i, j].axis('off')
                cnt += 1
        fig.savefig("mnist_%d.png" % epoch)
        plt.close()
Beispiel #16
0
def main():

    #----------
    # Conv Net
    #----------

    optimizer = Adam()

    data = datasets.load_digits()
    X = data.data
    y = data.target

    # Convert to one-hot encoding
    y = to_categorical(y.astype("int"))

    n_samples = np.shape(X)
    n_hidden = 512

    X_train, X_test, y_train, y_test = train_test_split(X,
                                                        y,
                                                        test_size=0.4,
                                                        seed=1)

    # Reshape X to (n_samples, channels, height, width)
    X_train = X_train.reshape((-1, 1, 8, 8))
    X_test = X_test.reshape((-1, 1, 8, 8))

    clf = NeuralNetwork(optimizer=optimizer,
                        loss=CrossEntropy,
                        validation_data=(X_test, y_test))

    clf.add(
        Conv2D(n_filters=16,
               filter_shape=(3, 3),
               input_shape=(1, 8, 8),
               padding='same'))
    clf.add(Activation('relu'))
    clf.add(Dropout(0.25))
    clf.add(BatchNormalization())
    clf.add(Conv2D(n_filters=32, filter_shape=(3, 3), padding='same'))
    clf.add(Activation('relu'))
    clf.add(Dropout(0.25))
    clf.add(BatchNormalization())
    clf.add(Flatten())
    clf.add(Dense(256))
    clf.add(Activation('relu'))
    clf.add(Dropout(0.5))
    clf.add(BatchNormalization())
    clf.add(Dense(10))
    clf.add(Activation('softmax'))

    print()
    clf.summary(name="ConvNet")

    train_err, val_err = clf.fit(X_train, y_train, n_epochs=50, batch_size=256)

    # Training and validation error plot
    n = len(train_err)
    training, = plt.plot(range(n), train_err, label="Training Error")
    validation, = plt.plot(range(n), val_err, label="Validation Error")
    plt.legend(handles=[training, validation])
    plt.title("Error Plot")
    plt.ylabel('Error')
    plt.xlabel('Iterations')
    plt.show()

    # Predict labels of the test data
    y_pred = np.argmax(clf.predict(X_test), axis=1)
    y_test = np.argmax(y_test, axis=1)

    accuracy = accuracy_score(y_test, y_pred)
    print("Accuracy:", accuracy)

    # Flatten data set
    X_test = X_test.reshape(-1, 8 * 8)

    # Reduce dimension to 2D using PCA and plot the results
    Plot().plot_in_2d(X_test,
                      y_pred,
                      title="Convolutional Neural Network",
                      accuracy=accuracy,
                      legend_labels=range(10))