Sigmoid Class Reference

A class that implements the Sigmoid activation function, inheriting from MLFunction. More...

#include <functions.h>

Inheritance diagram for Sigmoid:

Public Member Functions
	Sigmoid ()
	Default constructor.
void	apply (const SelectivityVector &rows, std::vector< VectorPtr > &args, const TypePtr &type, exec::EvalCtx &context, VectorPtr &output) const override
	Applies the Sigmoid function to the input array.
float *	getTensor () const override
	Returns the tensor associated with this function.
std::string	getFuncName ()
	Returns the name of the function.
CostEstimate	getCost (std::vector< int > inputDims)
	Estimates the computational cost of applying the Sigmoid function.
Public Member Functions inherited from MLFunction
virtual	~MLFunction ()=default
	Virtual destructor.
virtual std::vector< int >	getDims ()
	Returns the dimensions of the function.
virtual int	getNumDims ()
	Returns the number of dimensions of the function.

Static Public Member Functions
static float	sigmoidFunction (float x)
	Computes the Sigmoid function for a single input value.
static std::vector< std::shared_ptr< exec::FunctionSignature > >	signatures ()
	Returns the function signatures supported by this class.
static std::string	getName ()
	Static method to return the name of the function.

Additional Inherited Members
Protected Member Functions inherited from MLFunction
double	getWeightedCost (std::string name, float cost)
	Calculates the weighted cost of the function.
std::vector< double >	getCoefficientVector (std::string name)
	Retrieves the cost coefficients for the function.
Protected Attributes inherited from MLFunction
std::vector< int >	dims
	Dimensions of the function.

Detailed Description

A class that implements the Sigmoid activation function, inheriting from MLFunction.

The Sigmoid function maps input values to a range between 0 and 1. This class provides functionality to apply the Sigmoid function element-wise to an input array and produce an output array.

Member Function Documentation

apply()

void Sigmoid::apply ( const SelectivityVector & rows, std::vector< VectorPtr > & args, const TypePtr & type, exec::EvalCtx & context, VectorPtr & output ) const

inlineoverride

Applies the Sigmoid function to the input array.

This method processes the input array, applies the Sigmoid function element-wise, and stores the result in the output vector.

Parameters

rows	A SelectivityVector specifying the rows to process.
args	A vector of input arguments (e.g., the input array).
type	The type of the output vector.
context	The execution context.
output	The output vector where the result will be stored.

getCost()

CostEstimate Sigmoid::getCost ( std::vector< int > inputDims )

inlinevirtual

Estimates the computational cost of applying the Sigmoid function.

Parameters

inputDims

A vector containing the dimensions of the input.

Returns

A CostEstimate object representing the estimated cost.

Reimplemented from MLFunction.

getFuncName()

std::string Sigmoid::getFuncName ( )

inlinevirtual

Returns the name of the function.

Returns

The name of the function as a string.

Reimplemented from MLFunction.

getName()

static std::string Sigmoid::getName ( )

inlinestatic

Static method to return the name of the function.

Returns

The name of the function as a string ("sigmoid").

getTensor()

float * Sigmoid::getTensor ( ) const

inlineoverridevirtual

Returns the tensor associated with this function.

Returns

A pointer to an empty float array (no weights for Sigmoid).

Implements MLFunction.

sigmoidFunction()

static float Sigmoid::sigmoidFunction ( float x )

inlinestatic

Computes the Sigmoid function for a single input value.

Parameters

x	The input value.

Returns

The result of the Sigmoid function: 1.0f / (1.0f + exp(-x)).

signatures()

static std::vector< std::shared_ptr< exec::FunctionSignature > > Sigmoid::signatures ( )

inlinestatic

Returns the function signatures supported by this class.

Returns

A vector of shared pointers to FunctionSignature objects.

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The documentation for this class was generated from the following file:

• functions.h