vita::terminal Class Reference

A symbol with zero-arity. More...

#include <terminal.h>

Inherits vita::symbol.

Inherited by vita::ga::detail::number< int >, vita::ga::detail::number< double >, vita::boolean::one, vita::boolean::zero, vita::constant< T >, vita::constant< std::string >, vita::ga::detail::number< T >, vita::integer::number, vita::real::integer, vita::real::real, and vita::variable.

Public Member Functions
unsigned	arity () const final
virtual std::string	display (terminal_param_t, format=c_format) const
virtual terminal_param_t	init () const
	Used to initialize the internal parameter of the terminal. More...
virtual bool	parametric () const
	A parametric terminal needs an additional parameter to be evaluated. More...
	symbol (const std::string &, category_t=0)
Public Member Functions inherited from vita::symbol
virtual unsigned	arity () const =0
category_t	category () const
	The type (a.k.a. More...
void	category (category_t)
	Changes the category of a symbol. More...
virtual value_t	eval (symbol_params &) const =0
	Calculates the value of / performs the action associated with the symbol (it's implementation specific). More...
virtual bool	input () const
	An input variable is a feature from the learning domain. More...
virtual bool	is_valid () const
std::string	name () const
opcode_t	opcode () const
	An opcode is a unique, numerical session ID for a symbol. More...
double	penalty (core_interpreter *) const
	Used for automatic calculation of penalities due to broken constraints. More...
	symbol (const std::string &, category_t=0)
bool	terminal () const

Static Public Member Functions
static const terminal *	cast (const symbol *)
	This is a short cut function. More...

Additional Inherited Members
Public Types inherited from vita::symbol
enum	format {   c_format , cpp_format , mql_format , python_format ,   sup_format }
	Symbol rendering format. More...

Detailed Description

A symbol with zero-arity.

A terminal might be a variable (input to the program), a constant value or a function taking no arguments (e.g. move-north).

Examples

example6.cc.

Definition at line 26 of file terminal.h.

Member Function Documentation

arity()

unsigned vita::terminal::arity ( ) const

inlinefinalvirtual

Returns

0 (this is a terminal!)

Implements vita::symbol.

Definition at line 46 of file terminal.h.

cast()

const terminal * vita::terminal::cast ( const symbol *  s )

inlinestatic

This is a short cut function.

Parameters

[in]

s

symbol pointer

Returns

s casted to a vita::terminal pointer

Definition at line 83 of file terminal.h.

display()

std::string vita::terminal::display ( terminal_param_t  v, format  = c_format  ) const

virtual

Parameters

[in]

v

additional informations regarding parametric symbols

Returns

a string representing the symbol

The v argument is required for parametric symbols (i.e. for a numeric terminal we have to print 123 rather than "NUMBER").

Reimplemented in vita::integer::number, vita::real::real, vita::real::integer, vita::boolean::zero, vita::boolean::one, vita::constant< T >, vita::constant< std::string >, and vita::variable.

Definition at line 24 of file terminal.cc.

init()

terminal_param_t vita::terminal::init ( ) const

inlinevirtual

Used to initialize the internal parameter of the terminal.

Returns

0.0

Remarks

Derived classes should redefine this member function in a meaningful way.

Reimplemented in vita::integer::number, vita::real::real, and vita::real::integer.

Definition at line 72 of file terminal.h.

parametric()

bool vita::terminal::parametric ( ) const

inlinevirtual

A parametric terminal needs an additional parameter to be evaluated.

Returns

true for parametric symbols

Genes associated with parametric symbols store an additional parameter fetched at run-time and used for symbol evaluation.

Reimplemented in vita::integer::number, vita::real::real, and vita::real::integer.

Definition at line 59 of file terminal.h.

symbol()

vita::symbol::symbol ( const std::string &  name, category_t  c = 0  )

explicit

Parameters

[in]	name	name of the symbol
[in]	c	category of the symbol

Note

By default a symbol:

• is NOT associative;
• is NOT an input;
• is NOT parametric. These are safe values for derived classes.

Warning

Since the name of the symbol is used for serialization, it must be unique. Even the opcode is unique, but it can change between executions.

Definition at line 41 of file symbol.cc.

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

• terminal.h
• terminal.cc