athena__full_layer Module

Module containing implementation of a fully connected layer

This module implements a fully connected (dense) layer, the fundamental building block of neural networks that connects every input to every output.

Mathematical operation:

where: - is the input vector - is the weight matrix - is the bias vector - is the activation function - is the output vector

Number of parameters: (if bias used)

Properties: Universal function approximator (with sufficient width/depth) Learns arbitrary non-linear mappings between input and output spaces

Attribution statement: The get_num_params procedure is based on code from the neural-fortran library https://github.com/modern-fortran/neural-fortran



Interfaces

public interface full_layer_type

Interface for setting up the fully connected layer

  • private module function layer_setup(num_outputs, num_inputs, use_bias, activation, kernel_initialiser, bias_initialiser, verbose) result(layer)

    Setup a fully connected layer

    Arguments

    Type IntentOptional Attributes Name
    integer, intent(in) :: num_outputs

    Number of outputs

    integer, intent(in), optional :: num_inputs

    Number of inputs

    logical, intent(in), optional :: use_bias

    Whether to use bias

    class(*), intent(in), optional :: activation

    Activation function

    class(*), intent(in), optional :: kernel_initialiser

    Kernel and bias initialisers

    class(*), intent(in), optional :: bias_initialiser

    Kernel and bias initialisers

    integer, intent(in), optional :: verbose

    Verbosity level

    Return Value type(full_layer_type)

    Instance of the fully connected layer


Derived Types

type, public, extends(learnable_layer_type) ::  full_layer_type

Type for fully connected (aka dense) layer with overloaded procedures

Components

Type Visibility Attributes Name Initial
class(base_actv_type), public, allocatable :: activation

Activation function

class(base_init_type), public, allocatable :: bias_init

Initialisers for kernel and bias

character(len=14), public :: bias_initialiser = ''

Initialisers for kernel and bias

integer, public, allocatable, dimension(:) :: bias_shape

Shape of biases

type(graph_type), public, allocatable, dimension(:) :: graph

Graph structure of input data

integer, public :: id

Unique identifier

logical, public :: inference = .false.

Inference mode

integer, public :: input_rank = 0

Rank of input data

integer, public, allocatable, dimension(:) :: input_shape

Input shape

class(base_init_type), public, allocatable :: kernel_init

Initialisers for kernel and bias

character(len=14), public :: kernel_initialiser = ''

Initialisers for kernel and bias

character(len=:), public, allocatable :: name

Layer name

integer, public :: num_inputs

Number of inputs

integer, public :: num_outputs

Number of outputs

integer, public :: num_params = 0

Number of learnable parameters

class(array_type), public, allocatable, dimension(:,:) :: output

Output

integer, public :: output_rank = 0

Rank of output data

integer, public, allocatable, dimension(:) :: output_shape

Output shape

type(array_type), public, allocatable, dimension(:) :: params

Learnable parameters

character(len=20), public :: subtype = repeat(" ", 20)
character(len=4), public :: type = 'base'

Layer type

logical, public :: use_bias = .false.

Layer has bias

logical, public :: use_graph_input = .false.

Use graph input

logical, public :: use_graph_output = .false.

Use graph output

integer, public, allocatable, dimension(:,:) :: weight_shape

Shape of weights

type(array_type), public, dimension(1) :: z

Temporary arrays for forward propagation

Constructor

Interface for setting up the fully connected layer

private module function layer_setup (num_outputs, num_inputs, use_bias, activation, kernel_initialiser, bias_initialiser, verbose)

Setup a fully connected layer

Finalizations Procedures

final :: finalise_full

Finalise fully connected layer

Type-Bound Procedures

procedure, public :: add_t_t => add_learnable

Add two layers

procedure, public, pass(this) :: build_from_onnx => build_from_onnx_full

Build fully connected layer from ONNX node and initialiser

procedure, public, pass(this) :: emit_onnx_graph_inputs => emit_onnx_graph_inputs_base

Emit graph input tensor declarations for this layer

procedure, public, pass(this) :: emit_onnx_nodes => emit_onnx_nodes_base

Emit ONNX JSON nodes for this layer (format-aware and polymorphic)

procedure, public, pass(this) :: extract_output => extract_output_base

Extract the output of the layer as a standard real array

procedure, public, pass(this) :: forward => forward_full

Forward propagation derived type handler

procedure, public, pass(this) :: forward_eval => forward_eval_base

Forward pass of layer and return output for evaluation

procedure, public, pass(this) :: get_attributes => get_attributes_base

Get the attributes of the layer (for ONNX export)

procedure, public, pass(this) :: get_gradients

Get parameter gradients of layer

procedure, public, pass(this) :: get_num_params => get_num_params_full

Get the number of parameters for fully connected layer

procedure, public, pass(this) :: get_params

Get learnable parameters of layer

procedure, public, pass(this) :: init => init_full

Initialise fully connected layer

procedure, public, pass(this) :: nullify_graph => nullify_graph_base

Nullify the forward pass data of the layer to free memory

Read more…
generic, public :: operator(+) => add_t_t

Operator overloading for addition

procedure, public, pass(this) :: print => print_base

Print the layer to a file with additional information

procedure, public, pass(this) :: print_to_unit => print_to_unit_full

Print the layer to a file

procedure, public, pass(this) :: read => read_full

Read the layer from a file

procedure, public, pass(this) :: reduce => reduce_learnable

Merge another learnable layer into this one

procedure, public, pass(this) :: set_gradients

Set learnable parameters of layer

procedure, public, pass(this) :: set_graph => set_graph_base

Set the graph structure of the input data !! this is adjacency and edge weighting

procedure, public, pass(this) :: set_hyperparams => set_hyperparams_full

Set the hyperparameters for fully connected layer

procedure, public, pass(this) :: set_params

Set learnable parameters of layer

procedure, public, pass(this) :: set_rank => set_rank_base

Set the input and output ranks of the layer

procedure, public, pass(this) :: set_shape => set_shape_base

Set the input shape of the layer


Functions

public function create_from_onnx_full_layer(node, initialisers, value_info, verbose) result(layer)

Build fully connected layer from attributes and return layer

Arguments

Type IntentOptional Attributes Name
type(onnx_node_type), intent(in) :: node

Instance of ONNX node information

type(onnx_initialiser_type), intent(in), dimension(:) :: initialisers

Instance of ONNX initialiser information

type(onnx_tensor_type), intent(in), dimension(:) :: value_info

Instance of ONNX value info information

integer, intent(in), optional :: verbose

Verbosity level

Return Value class(base_layer_type), allocatable

Instance of the 2D convolutional layer

public function read_full_layer(unit, verbose) result(layer)

Read fully connected layer from file and return layer

Arguments

Type IntentOptional Attributes Name
integer, intent(in) :: unit

Unit number

integer, intent(in), optional :: verbose

Verbosity level

Return Value class(base_layer_type), allocatable

Instance of the fully connected layer

private pure function get_num_params_full(this) result(num_params)

Get the number of parameters for fully connected layer

Read more…

Arguments

Type IntentOptional Attributes Name
class(full_layer_type), intent(in) :: this

Instance of the fully connected layer

Return Value integer

Number of parameters

private module function layer_setup(num_outputs, num_inputs, use_bias, activation, kernel_initialiser, bias_initialiser, verbose) result(layer)

Setup a fully connected layer

Arguments

Type IntentOptional Attributes Name
integer, intent(in) :: num_outputs

Number of outputs

integer, intent(in), optional :: num_inputs

Number of inputs

logical, intent(in), optional :: use_bias

Whether to use bias

class(*), intent(in), optional :: activation

Activation function

class(*), intent(in), optional :: kernel_initialiser

Activation function, kernel initialiser, and bias initialiser

class(*), intent(in), optional :: bias_initialiser

Activation function, kernel initialiser, and bias initialiser

integer, intent(in), optional :: verbose

Verbosity level

Return Value type(full_layer_type)

Instance of the fully connected layer


Subroutines

private subroutine build_from_onnx_full(this, node, initialisers, value_info, verbose)

Read ONNX attributes for fully connected layer

Arguments

Type IntentOptional Attributes Name
class(full_layer_type), intent(inout) :: this

Instance of the fully connected layer

type(onnx_node_type), intent(in) :: node

Instance of ONNX node information

type(onnx_initialiser_type), intent(in), dimension(:) :: initialisers

Instance of ONNX initialiser information

type(onnx_tensor_type), intent(in), dimension(:) :: value_info

Instance of ONNX value info information

integer, intent(in) :: verbose

Verbosity level

private subroutine finalise_full(this)

Finalise fully connected layer

Arguments

Type IntentOptional Attributes Name
type(full_layer_type), intent(inout) :: this

Instance of the fully connected layer

private subroutine forward_full(this, input)

Forward propagation

Arguments

Type IntentOptional Attributes Name
class(full_layer_type), intent(inout) :: this

Instance of the fully connected layer

class(array_type), intent(in), dimension(:,:) :: input

Input values

private subroutine init_full(this, input_shape, verbose)

Initialise fully connected layer

Arguments

Type IntentOptional Attributes Name
class(full_layer_type), intent(inout) :: this

Instance of the fully connected layer

integer, intent(in), dimension(:) :: input_shape

Input shape

integer, intent(in), optional :: verbose

Verbosity level

private subroutine print_to_unit_full(this, unit)

Print fully connected layer to unit

Arguments

Type IntentOptional Attributes Name
class(full_layer_type), intent(in) :: this

Instance of the fully connected layer

integer, intent(in) :: unit

File unit

private subroutine read_full(this, unit, verbose)

Read fully connected layer from file

Arguments

Type IntentOptional Attributes Name
class(full_layer_type), intent(inout) :: this

Instance of the fully connected layer

integer, intent(in) :: unit

Unit number

integer, intent(in), optional :: verbose

Verbosity level

private subroutine set_hyperparams_full(this, num_outputs, use_bias, activation, kernel_initialiser, bias_initialiser, verbose)

Set the hyperparameters for fully connected layer

Arguments

Type IntentOptional Attributes Name
class(full_layer_type), intent(inout) :: this

Instance of the fully connected layer

integer, intent(in) :: num_outputs

Number of outputs

logical, intent(in) :: use_bias

Whether to use bias

class(base_actv_type), intent(in), allocatable :: activation

Activation function

class(base_init_type), intent(in), allocatable :: kernel_initialiser

Kernel and bias initialisers

class(base_init_type), intent(in), allocatable :: bias_initialiser

Kernel and bias initialisers

integer, intent(in), optional :: verbose

Verbosity level