Showing posts with label Generative models. Show all posts
Showing posts with label Generative models. Show all posts

Monday, January 22, 2024

Foundation of Geometric Learning

Target audience: Beginner
Estimated reading time: 4'
Newsletter: Geometric Learning in Python   
     
Facing challenges with high-dimensional, densely packed but limited data, and complex distributions? Differential geometry offers a solution by enabling data scientists to grasp the true shape and distribution of data.

Table of contents
      Deep learning
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What you will learn: You'll discover how differential geometry tackles the challenges of scarce data, high dimensionality, and the demand for independent representation in creating advanced machine learning models, such as graph or physics-informed neural networks.

Note: 
This article does not deal with the mathematical formalism of differential geometry or its implementation in Python.


Challenges 

Deep learning

Data scientists face challenges when building deep learning models that can be addressed by differential geometry. Those challenges are:
  • High dimensionality: Models related to computer vision or images deal with high-dimensional data, such as images or videos, which can make training more difficult due to the curse of dimensionality.
  • Availability of quality data: The quality and quantity of training data significantly affect the model's ability to generate realistic samples. Insufficient or biased data can lead to overfitting or poor generalization.
  • Underfitting or overfitting: Balancing the model's ability to generalize well while avoiding overfitting to the training data is a critical challenge. Models that overfit may generate high-quality outputs that are too similar to the training data, lacking novelty.
  • Embedding physics law or geometric constraints: Incorporating domain constraints such as boundary conditions or differential equations model s very challenging for high-dimensional data.
  • Representation dependence: The performance of many learning algorithms is very sensitive to the choice of representation (i.e. z-normalization impact on predictors).

Generative modeling

Generative modeling includes techniques such as auto-encoders, generative adversarial networks (GANs), Markov chains, transformers, and their various derivatives.

Creating generative models presents several specific challenges beyond plain vanilla deep learning models for data scientists and engineers, primarily due to the complexity of modeling and generating data that accurately reflects real-world distributions. The challenges that can be addressed with differential geometry include:
  • Performance evaluation: Unlike supervised learning models, assessing the performance of generative models is not straightforward. Traditional metrics like accuracy do not apply, leading to the development of alternative metrics such as the Frechet Inception Distance (FID) or Inception Score, which have their limitations.
  • Latent space interpretability: Understanding and interpreting the latent space of generative models, where the model learns a compressed representation of the data, can be challenging but is crucial for controlling and improving the generation process.


What is differential geometry

Differential geometry is a branch of mathematics that uses techniques from calculus, algebra and topology to study the properties of curves, surfaces, and higher-dimensional objects in space. It focuses on concepts such as curvature, angles, and distances, examining how these properties vary as one moves along different paths on a geometric object [ref 1]. 
Differential geometry is crucial in understanding the shapes and structures of objects that can be continuously altered, and it has applications in many fields including physics (I.e., general relativity and quantum mechanics), engineering, computer science, and data exploration and analysis.

Moreover, it is important to differentiate between differential topology and differential geometry, as both disciplines examine the characteristics of differentiable (or smooth) manifolds but aim for different goals. Differential topology is concerned with the overarching structure or global aspects of a manifold, whereas differential geometry investigates the manifold's local and differential attributes, including aspects like connection and metric [ref 2].

In summary differential geometry provides data scientists with a mathematical framework facilitates the creation of models that are accurate and complex by leveraging geometric and topological insights [ref 3].


Applicability of differential geometry

Why differential geometry?

The following highlights the advantages of utilizing differential geometry to tackle the difficulties encountered by researchers in the creation and validation of generative models.

Understanding data manifolds: Data in high-dimensional spaces often lie on lower-dimensional manifolds. Differential geometry provides tools to understand the shape and structure of these manifolds, enabling generative models to learn more efficient and accurate representations of data.

Improving latent space interpolation: In generative models, navigating the latent space smoothly is crucial for generating realistic samples. Differential geometry offers methods to interpolate more effectively within these spaces, ensuring smoother transitions and better quality of generated samples.

Optimization on manifolds: The optimization processes used in training generative models can be enhanced by applying differential geometric concepts. This includes optimizing parameters directly on the manifold structure of the data or model, potentially leading to faster convergence and better local minima.

Geometric regularization: Incorporating geometric priors or constraints based on differential geometry can help in regularizing the model, guiding the learning process towards more realistic or physically plausible solutions, and avoiding overfitting.

Advanced sampling techniques: Differential geometry provides sophisticated techniques for sampling from complex distributions (important for both training and generating new data points), improving upon traditional methods by considering the underlying geometric properties of the data space.

Enhanced model interpretability: By leveraging the geometric structure of the data and model, differential geometry can offer new insights into how generative models work and how their outputs relate to the input data, potentially improving interpretability.

Physics-Informed Neural Networks:  Projecting physics law and boundary conditions such as set of partial differential equations on a surface manifold improves the optimization of deep learning models.

Innovative architectures: Insights from differential geometry can lead to the development of novel neural network architectures that are inherently more suited to capturing the complexities of data manifolds, leading to more powerful and efficient generative models. 

In summary, differential geometry equips researchers and practitioners with a deep toolkit for addressing the intrinsic challenges of generative AI, from better understanding and exploring complex data landscapes to developing more sophisticated and effective models [ref 3].

Representation independence

The effectiveness of many learning models greatly depends on how the data is represented, such as the impact of z-normalization on predictors. Representation Learning is the technique in machine learning that identifies and utilizes meaningful patterns from raw data, creating more accessible and manageable representations. Deep neural networks, as models of representation learning, typically transform and encode information into a different subspace. 
In contrast, differential geometry focuses on developing constructs that remain consistent regardless of the data representation method. It gives us a way to construct objects which are intrinsic to the manifold itself [ref 4].

Manifold and latent space

A manifold is essentially a space that, around every point, looks like Euclidean space, created from a collection of maps (or charts) called an atlas, which belongs to Euclidean space. Differential manifolds have a tangent space at each point, consisting of vectors. Riemannian manifolds are a type of differential manifold equipped with a metric to measure curvature, gradient, and divergence. 
In deep learning, the manifolds of interest are typically Riemannian due to these properties.

It is important to keep in mind that the goal of any machine learning or deep learning model is to predict p(y) from p(y|x) for observed features y given latent features x.\[p(y)=\int_{\Omega }^{} p(y|x).p(x)dx\].The latent space x can be defined as a differential manifold embedding in the data space (number of features of the input data).
Given a differentiable function f on a domain  a manifold of dimension d is defined by:
\[\mathit{M}=f(\Omega) \ \ \ with \ f: \Omega \subset \mathbb{R}^{d}\rightarrow \mathbb{R}^{d}\]
In a Riemannian manifold, the metric can be used to 
  • Estimate kernel density
  • Approximate the encoder function of an auto-encoder
  • Represent the vector space defined by classes/labels in a classifier
A manifold is usually visualized with a tangent space at give point/coordinates.

Illustration of a manifold and its tangent space


The manifold hypothesis states that real-world high-dimensional data lie on low-dimensional manifolds embedded within the high-dimensional space.

Studying data that reside on manifolds can often be done without the need for Riemannian Geometry, yet opting to perform data analysis on manifolds presents three key advantages [ref 5]:
  • By analyzing data directly on its residing manifold, you can simplify the system by reducing its degrees of freedom. This simplification not only makes calculations easier but also results in findings that are more straightforward to understand and interpret.
  • Understanding the specific manifold to which a dataset belongs enhances your comprehension of how the data evolves over time.
  • Being aware of the manifold on which a dataset exists enhances your ability to predict future data points. This knowledge allows for more effective signal extraction from datasets that are either noisy or contain limited data points.

Graph Neural Networks

Graph Neural Networks (GNNs) are a type of deep learning models designed to perform inference on data represented as graphs. They are particularly effective for tasks where the data is structured in a non-Euclidean manner, capturing the relationships and interactions between nodes in a graph.

Graph Neural Networks operate by conducting message passing across a graph, in which features are transmitted from one node to another through the connecting edges (diffusion process). For instance, the concept of Ricci curvature from differential geometry helps to alleviate congestion in the flow of messages [ref 6].

Physics-Informed Neural Networks

Physics-informed neural networks (PINNs) are versatile models capable of integrating physical principles, governed by partial differential equations, into the learning mechanism. They utilize these physical laws as a form of soft constraint or regularization during training, effectively addressing the challenge of limited data in certain engineering applications [ref 7].

Information geometry

Information geometry is a field that combines ideas from differential geometry and information theory to study the geometric structure of probability distributions and statistical models. It focuses on the way information can be quantified, manipulated, and interpreted geometrically, exploring concepts like distance and curvature within the space of probability distributions. 
This approach provides a powerful framework for understanding complex statistical models and the relationships between them, making it applicable in areas such as machine learning, signal processing, and more [ref 8].


Python libraries for differential geometry

There are numerous open-source Python libraries available, with a variety of focuses not exclusively tied to machine learning or generative modeling:

References

[8] Information Geometry: Near Randomness and Near Independence - 
      K. Arvin, CT Dodson - Springer-Verlag 2008



-------------
Patrick Nicolas has over 25 years of experience in software and data engineering, architecture design and end-to-end deployment and support with extensive knowledge in machine learning. 
He has been director of data engineering at Aideo Technologies since 2017 and he is the author of "Scala for Machine Learning", Packt Publishing ISBN 978-1-78712-238-3 and Geometric Learning in Python Newsletter on LinkedIn.


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Saturday, September 11, 2021

Automate GAN Configuration in PyTorch

Target audience: Advanced
Estimated reading time: 5'

Working with the architecture and deployment of Generative Adversarial Networks (GANs) often involves complex details that can be difficult to understand and resolve. Consider the advantage of identifying neural components that are reusable and can be utilized in both the generator and discriminator parts of the network.


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Notes:
  • This post steers clear of the intricate technicalities of generative adversarial networks and convolutional neural networks. Instead, it focuses on automating the setup process for certain neural components.
  • Readers are expected to have a foundational knowledge of neural networks and familiarity with the PyTorch library.
  • Environments: Python 3.9, PyTorch 1.9.1

The challenge

This article is focused on streamlining the development of Deep Convolutional Generative Adversarial Networks (DCGANs) [ref 1]. We achieve this by configuring the generator in relation to the setup of the discriminator. The main area of our study is the well-known application of using GANs to differentiate between real and fake images.

For those unfamiliar with GANs..... 

Generative Adversarial Networks (GANs) [ref 2] are a type of unsupervised learning model that identify patterns within data and utilize these patterns for data augmentation, creating new samples that closely resemble the original dataset. GANs belong to the family of generative models, which also includes variational auto-encoders and maximum likelihood estimation (MLE) models. The unique aspect of GANs is that they convert the problem into a form of supervised learning by employing two competing networks:
  • The Generator model, which is trained to produce new data samples.
  • The Discriminator model, which aims to differentiate between real samples (from the original dataset) and fake ones (created by the Generator).
Crafting and setting up components like the generator and discriminator in a Generative Adversarial Network (GAN), or the encoder and decoder layers in a Variational Convolutional Auto-Encoder (VAE), can often be a repetitive and laborious process.

In fact, some aspects of this process can be entirely automated. For instance, the generative network in a convolutional GAN can be designed as the inverse of the discriminator using a de-convolutional network. Similarly, the decoder in a VAE can be automatically configured based on the structure of its encoder.

Functional representation of a simple deep convolutional GAN


Neural component reusability is key to generate a de-convolutional network from a convolutional network. To this purpose we break down a neural network into computational blocks.

Convolutional networks

In its most basic form, a Generative Adversarial Network (GAN) consists of two distinct neural networks: a generator and a discriminator.

Neural blocks

Each of these networks is further subdivided into neural blocks or groups of PyTorch modules, which include elements like hidden layers, batch normalization, regularization, pooling modes, and activation functions. Take, for example, a discriminator that is structured using a convolutional neural network [ref 3] followed by a fully connected (restricted Boltzmann machine) network. The PyTorch modules corresponding to each layer are organized into what we call a neural block class.

A PyTorch modules of the convolutional neural block [ref 4] are:
  • Conv2d: Convolutional layer with input, output channels, kernel, stride and padding
  • Dropout: Drop-out regularization layer
  • BatchNorm2d: Batch normalization module
  • MaxPool2d Pooling layer
  • ReLu, Sigmoid, ... Activation functions
Representation of a convolutional neural block with PyTorch modules

The constructor of the neural block is designed to initialize all its parameters and modules in the correct sequence. For simplicity, we are not including regularization elements like drop-out (which essentially involves bagging of sub-networks) in this setup.

Important note: Each step of the algorithm makes reference to comments in the code (i.e.  The first step [1] is to initialize the number of input and output channels refers to  # [1] - initialize the input and output channels).

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class ConvNeuralBlock(nn.Module):

  def __init__(self,
      in_channels: int,
      out_channels: int,
      kernel_size: int,
      stride: int,
      padding: int,
      batch_norm: bool,
      max_pooling_kernel: int,
      activation: nn.Module,
      bias: bool,
      is_spectral: bool = False):
    
   super(ConvNeuralBlock, self).__init__()
        
   # Assertions are omitted
   # [1] - initialize the input and output channels
   self.in_channels = in_channels
   self.out_channels = out_channels
   self.is_spectral = is_spectral
   modules = []
   
   # [2] - create a 2 dimension convolution layer
   conv_module = nn.Conv2d(   
       self.in_channels,
       self.out_channels,
       kernel_size=kernel_size,
       stride=stride,
       padding=padding,
       bias=bias)

   # [6] - if this is a spectral norm block
   if self.is_spectral:        
      conv_module = nn.utils.spectral_norm(conv_module)
      modules.append(conv_module)
        
   # [3] - Batch normalization
   if batch_norm:               
      modules.append(nn.BatchNorm2d(self.out_channels))
      
   # [4] - Activation function
   if activation is not None: 
      modules.append(activation)
         
   # [5] - Pooling module
   if max_pooling_kernel > 0:   
      modules.append(nn.MaxPool2d(max_pooling_kernel))
   
   self.modules = tuple(modules)

We considering the case of a generative model for images. The first step [#1] is to initialize the number of input and output channels, then create the 2-dimension convolution [#2], a batch normalization module [#3] an activation function [#4] and finally a max pooling module [#5]. The spectral norm regularization term [#6] is optional.
The convolutional neural network is assembled from convolutional and feedback forward neural blocks, in the following build method.

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class ConvModel(NeuralModel):

  def __init__(self,                    
       model_id: str,
       # [1] - Number of input and output unites
       input_size: int,
       output_size: int,
       # [2] - PyTorch convolutional modules
       conv_model: nn.Sequential,
       dff_model_input_size: int = -1,
       # [3] - PyTorch fully connected
       dff_model: nn.Sequential = None):
        
   super(ConvModel, self).__init__(model_id)
   self.input_size = input_size
   self.output_size = output_size
   self.conv_model = conv_model
   self.dff_model_input_size = dff_model_input_size
   self.dff_model = dff_model
   
  @classmethod
  def build(cls,
      model_id: str,
      conv_neural_blocks: list,  
      dff_neural_blocks: list) -> NeuralModel:
            
   # [4] - Initialize the input and output size 
   #        for the convolutional layer
   input_size = conv_neural_blocks[0].in_channels
   output_size = conv_neural_blocks[len(conv_neural_blocks) - 1].out_channels

   # [5] - Generate the model from the sequence 
   #        of conv. neural blocks
   conv_modules = [conv_module for conv_block in conv_neural_blocks
         for conv_module in conv_block.modules]
   conv_model = nn.Sequential(*conv_modules)

   # [6] - If a fully connected RBM is included in the model ..
   if dff_neural_blocks is not None and not is_vae:
      dff_modules = [dff_module for dff_block in dff_neural_blocks
          for dff_module in dff_block.modules]
         
      dff_model_input_size = dff_neural_blocks[0].output_size
      dff_model = nn.Sequential(*tuple(dff_modules))
   else:
      dff_model_input_size = -1
      dff_model = None
      
  return cls(
     model_id, 
     conv_dimension, 
     input_size, 
     output_size, 
     conv_model,
     dff_model_input_size, 
     dff_model)

The standard constructor [#1] sets up the count of input/output channels, along with the PyTorch modules for the convolutional layers [#2] and the fully connected layers [#3].
The class method, build, creates the convolutional model using convolutional neural blocks and feed-forward neural blocks. It determines the dimensions of the input and output layers based on the first and last neural blocks [#4], and then produces the PyTorch convolutional modules [#5] and modules for fully-connected layers [#6] from these neural blocks.

Following this, we proceed to construct the de-convolutional neural network utilizing the convolutional blocks.

Inverting a convolutional block

To build a GAN, one must follow these steps:
  1. Select and specify the PyTorch modules that will constitute each convolutional layer.
  2. Assemble these chosen modules into a single convolutional neural block.
  3. Construct the generator and discriminator of the GAN by integrating these neural blocks.
  4. Link the generator and discriminator to create a fully functional GAN.
The aim here is to create a builder capable of producing the de-convolutional network. This network will act as the GAN's generator, formulated on the basis of the convolutional network described in the preceding section.

The process begins with the extraction of the de-convolutional block from an already established convolutional block.
Conceptual automated generation of de-convolutional block

The standard constructor for the neural block in a de-convolutional network sets up all the essential parameters required for the network, with the exception of the pooling module (which is not necessary). The code example provided demonstrates how to create a De-convolutional neural block. This process involves using convolution parameters like the number of input and output channels, kernel size, stride, padding, along with batch normalization and the activation function.


class DeConvNeuralBlock(nn.Module):

  def __init__(self,
       in_channels: int,
       out_channels: int,
       kernel_size: int,
       stride: int,
       padding: int,
       batch_norm: bool,
       activation: nn.Module,
       bias: bool) -> object:
    super(DeConvNeuralBlock, self).__init__()
    self.in_channels = in_channels
    self.out_channels = out_channels
    modules = []
             
    # Two dimension de-convolution layer
    de_conv = nn.ConvTranspose2d(
       self.in_channels,
       self.out_channels,
       kernel_size=kernel_size,
       stride=stride, 
       padding=padding,
       bias=bias)
   # Add the deconvolution block
   modules.append(de_conv)

   # Add the batch normalization, if defined
   if batch_norm:         
      modules.append(nn.BatchNorm2d(self.out_channels))
   # Add activation
   modules.append(activation)
   self.modules = modules

Be aware that the de-convolution block lacks pooling capabilities. The class method named auto_build accepts a convolutional neural block, the number of input and output channels, and an optional activation function to create a de-convolutional neural block of the DeConvNeuralBlock type. The calculation of the number of input and output channels for the resulting deconvolution layer is handled by the private method __resize.


@classmethod
def auto_build(cls,
    conv_block: ConvNeuralBlock,
    in_channels: int,
    out_channels: int = None,
    activation: nn.Module = None) -> nn.Module:
    
  # Extract the parameters of the source convolutional block
  kernel_size, stride, padding, batch_norm, activation = \
      DeConvNeuralBlock.__resize(conv_block, activation)

  # Override the number of input_tensor channels 
  # for this block if defined
  next_block_in_channels = in_channels 
     if in_channels is not None \
     else conv_block.out_channels

  # Override the number of output-channels for 
  # this block if specified
  next_block_out_channels = out_channels 
     if out_channels is not None \
     else conv_block.in_channels
    
  return cls(
        conv_block.conv_dimension,
        next_block_in_channels,
        next_block_out_channels,
        kernel_size,
        stride,
        padding,
        batch_norm,
        activation,
        False)

Sizing de-convolutional layers

The next task consists of computing the size of the component of the de-convolutional block from the original convolutional block. 

@staticmethod
def __resize(
  conv_block: ConvNeuralBlock,
  updated_activation: nn.Module) -> (int, int, int, bool, nn.Module):
  conv_modules = list(conv_block.modules)
    
  # [1] - Extract the various components of the 
  #        convolutional neural block
  _, batch_norm, activation = DeConvNeuralBlock.__de_conv_modules(conv_modules)
  
  # [2] - override the activation function for the 
  #        output layer, if necessary
  if updated_activation is not None:
     activation = updated_activation
    
    # [3]- Compute the parameters for the de-convolutional 
    #       layer, from the conv. block
     kernel_size, _ = conv_modules[0].kernel_size
     stride, _ = conv_modules[0].stride
     padding = conv_modules[0].padding

 return kernel_size, stride, padding, batch_norm, activation


The __resize method performs several functions: it retrieves the PyTorch modules for the de-convolutional layers from the initial convolutional block [#1], incorporates the activation function into the block [#2], and ultimately sets up the parameters for the de-convolutional layer [#3].

Additionally, there's a utility method named __de_conf_modules. This method is responsible for extracting the PyTorch modules associated with the convolutional layer, the batch normalization module, and the activation function for the de-convolution, all from the convolution's PyTorch modules.

@staticmethod
def __de_conv_modules(conv_modules: list) -> \
        (torch.nn.Module, torch.nn.Module, torch.nn.Module):

  activation_function = None
  deconv_layer = None
  batch_norm_module = None

  # 4- Extract the PyTorch de-convolutional modules 
  #     from the convolutional ones
  for conv_module in conv_modules:
     if DeConvNeuralBlock.__is_conv(conv_module):
         deconv_layer = conv_module
     elif DeConvNeuralBlock.__is_batch_norm(conv_module):
         batch_norm_moduled = conv_module
     elif DeConvNeuralBlock.__is_activation(conv_module):
        activation_function = conv_module

  return deconv_layer, batch_norm_module, activation_function



Convolutional layers

and the height of the two dimension output data is



De-convolutional layers
As expected, the formula to compute the size of the output of a de-convolutional layer is the mirror image of the formula for the output size of the convolutional layer.

and


Assembling de-convolutional network

Finally, a de-convolutional model, categorized as DeConvModel, is constructed using a sequence of PyTorch modules, referred to as de_conv_model. The default constructor [#1] is used once more to establish the dimensions of the input layer [#2] and the output layer [#3]. It also loads the PyTorch modules, named de_conv_modules, for all the de-convolutional layers.

class DeConvModel(NeuralModel, ConvSizeParams):

  def __init__(self,            # [1] - Default constructor
           model_id: str,
           input_size: int,      # [2] - Size first layer
           output_size: int,    # [3] - Size output layer
           de_conv_modules: torch.nn.Sequential):
    super(DeConvModel, self).__init__(model_id)
    self.input_size = input_size
    self.output_size = output_size
    self.de_conv_modules = de_conv_modules


  @classmethod
  def build(cls,
      model_id: str,
      conv_neural_blocks: list,  # [4] - Input to the builder
      in_channels: int,
      out_channels: int = None,
      last_block_activation: torch.nn.Module = None) -> NeuralModel:
    
    de_conv_neural_blocks = []

    # [5] - Need to reverse the order of convolutional neural blocks
    list.reverse(conv_neural_blocks)

    # [6] - Traverse the list of convolutional neural blocks
    for idx in range(len(conv_neural_blocks)):
       conv_neural_block = conv_neural_blocks[idx]
       new_in_channels = None
       activation = None
       last_out_channels = None

        # [7] - Update num. input channels for the first 
        # de-convolutional layer
       if idx == 0:
            new_in_channels = in_channels
        
        # [8] - Defined, if necessary the activation 
        # function for the last layer
       elif idx == len(conv_neural_blocks) - 1:
          if last_block_activation is not None:
             activation = last_block_activation
          if out_channels is not None:
             last_out_channels = out_channels

        # [9] - Apply transposition to the convolutional block
      de_conv_neural_block = DeConvNeuralBlock.auto_build(
           conv_neural_block,
           new_in_channels,
           last_out_channels,
            activation)
      de_conv_neural_blocks.append(de_conv_neural_block)
        
       # [10]- Instantiate the Deconvolutional network 
       # from its neural blocks
   de_conv_model = DeConvModel.assemble(
       model_id, 
       de_conv_neural_blocks)
     
   del de_conv_neural_blocks
   return de_conv_model


The alternative constructor named build is designed to generate and set up the de-convolutional model using the convolutional blocks, referred to as conv_neural_blocks [#4].

To align the order of de-convolutional layers correctly, it's necessary to reverse the sequence of convolutional blocks [#5]. For every block within the convolutional network [#6], this method adjusts the number of input channels to match the number of input channels in the first layer [#7].

It then updates the activation function for the final output layer [#8] and systematically integrates the de-convolutional blocks [#9]. Ultimately, the de-convolutional neural network is composed using these blocks [#10]..

@classmethod
def assemble(cls, model_id: str, de_conv_neural_blocks: list):
   input_size = de_conv_neural_blocks[0].in_channels
   output_size = de_conv_neural_blocks[len(de_conv_neural_blocks)-1].out_channels 
 
   # [11]- Generate the PyTorch convolutional modules used by the default constructor
  conv_modules = tuple([conv_module for conv_block in de_conv_neural_blocks
                        for conv_module in conv_block.modules 
                        if conv_module is not None])
  de_conv_model = torch.nn.Sequential(*conv_modules)

  return cls(model_id, input_size, output_size, de_conv_model)

The assemble method is responsible for building the complete de-convolutional neural network. It does this by compiling the PyTorch modules from each of the blocks in de_conv_neural_blocks into a cohesive unit [#11].

Thank you for reading this article. For more information ...

References
[2] A Gentle Introduction to Generative Adversarial Networks
[3] Deep learning Chap 9 Convolutional networks. 
          I. Goodfellow, Y. Bengio, A. Courville - 2017 MIT Press Cambridge MA 


---------------------------
Patrick Nicolas has over 25 years of experience in software and data engineering, architecture design and end-to-end deployment and support with extensive knowledge in machine learning. 
He has been director of data engineering at Aideo Technologies since 2017 and he is the author of "Scala for Machine Learning" Packt Publishing ISBN 978-1-78712-238-3


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