A dimension of the vector space. More...

#include <Variable.defs.hh>

Classes
struct	Compare
	Binary predicate defining the total ordering on variables. More...
Public Types
typedef void	output_function_type (std::ostream &s, const Variable v)
	Type of output functions.
Public Member Functions
	Variable (dimension_type i)
	Builds the variable corresponding to the Cartesian axis of index `i`.
dimension_type	id () const
	Returns the index of the Cartesian axis associated to the variable.
dimension_type	space_dimension () const
	Returns the dimension of the vector space enclosing `*this`.
memory_size_type	total_memory_in_bytes () const
	Returns the total size in bytes of the memory occupied by `*this`.
memory_size_type	external_memory_in_bytes () const
	Returns the size in bytes of the memory managed by `*this`.
bool	OK () const
	Checks if all the invariants are satisfied.
Static Public Member Functions
static dimension_type	max_space_dimension ()
	Returns the maximum space dimension a Variable can handle.
static void	set_output_function (output_function_type *p)
	Sets the output function to be used for printing Variable objects.
static output_function_type *	get_output_function ()
	Returns the pointer to the current output function.
Static Private Member Functions
static void	default_output_function (std::ostream &s, const Variable v)
	The default output function.
Private Attributes
dimension_type	varid
	The index of the Cartesian axis.
Static Private Attributes
static output_function_type *	current_output_function = 0
	Pointer to the current output function.
Friends
class	Init
std::ostream &	Parma_Polyhedra_Library::IO_Operators::operator<< (std::ostream &s, const Variable v)
Related Functions
(Note that these are not member functions.)
std::ostream &	operator<< (std::ostream &s, const Variable v)
std::ostream &	operator<< (std::ostream &s, const Variable v)
	Output operator.
bool	less (Variable v, Variable w)
	Defines a total ordering on variables.
bool	less (const Variable v, const Variable w)

Detailed Description

A dimension of the vector space.

An object of the class Variable represents a dimension of the space, that is one of the Cartesian axes. Variables are used as basic blocks in order to build more complex linear expressions. Each variable is identified by a non-negative integer, representing the index of the corresponding Cartesian axis (the first axis has index 0). The space dimension of a variable is the dimension of the vector space made by all the Cartesian axes having an index less than or equal to that of the considered variable; thus, if a variable has index $i$ , its space dimension is $i+1$ .

Note that the ``meaning'' of an object of the class Variable is completely specified by the integer index provided to its constructor: be careful not to be mislead by C++ language variable names. For instance, in the following example the linear expressions e1 and e2 are equivalent, since the two variables x and z denote the same Cartesian axis.

  Variable x(0);
  Variable y(1);
  Variable z(0);
  Linear_Expression e1 = x + y;
  Linear_Expression e2 = y + z;

Definition at line 81 of file Variable.defs.hh.

Member Typedef Documentation

typedef void Parma_Polyhedra_Library::Variable::output_function_type(std::ostream &s, const Variable v)

Type of output functions.

Definition at line 114 of file Variable.defs.hh.

Constructor & Destructor Documentation

Parma_Polyhedra_Library::Variable::Variable ( dimension_type i )

inlineexplicit

Builds the variable corresponding to the Cartesian axis of index i.

Exceptions:

std::length_error Thrown if i+1 exceeds Variable::max_space_dimension().

Definition at line 38 of file Variable.inlines.hh.

  : varid((i < max_space_dimension())
          ? i
          : (throw std::length_error("PPL::Variable::Variable(i):\n"
                                     "i exceeds the maximum allowed "
                                     "variable identifier."), i)) {
}

Member Function Documentation

void Parma_Polyhedra_Library::Variable::default_output_function	(	std::ostream &	s,
		const Variable	v
	)

staticprivate

The default output function.

Definition at line 39 of file Variable.cc.

References id().

Referenced by Parma_Polyhedra_Library::Init::Init().

                                                                    {
  dimension_type varid = v.id();
  static const char var_name_letters[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
  const dimension_type num_letters = sizeof(var_name_letters) - 1;
  s << var_name_letters[varid % num_letters];
  if (dimension_type i = varid / num_letters)
    s << i;
}

memory_size_type Parma_Polyhedra_Library::Variable::external_memory_in_bytes ( ) const

inline

Returns the size in bytes of the memory managed by *this.

Definition at line 57 of file Variable.inlines.hh.

Referenced by total_memory_in_bytes().

                                         {
  return 0;
}

Variable::output_function_type * Parma_Polyhedra_Library::Variable::get_output_function ( )

inlinestatic

Returns the pointer to the current output function.

Definition at line 72 of file Variable.inlines.hh.

References current_output_function.

Referenced by Parma_Polyhedra_Library::Implementation::Termination::all_affine_quasi_ranking_functions_MS(), Parma_Polyhedra_Library::Implementation::Termination::all_affine_ranking_functions_MS(), Parma_Polyhedra_Library::Implementation::Termination::all_affine_ranking_functions_PR(), Parma_Polyhedra_Library::Implementation::Termination::fill_constraint_systems_MS(), Parma_Polyhedra_Library::Implementation::Termination::one_affine_ranking_function_PR(), and Parma_Polyhedra_Library::Implementation::Termination::termination_test_PR().

                              {
  return current_output_function;
}

dimension_type Parma_Polyhedra_Library::Variable::id ( ) const

inline

Returns the index of the Cartesian axis associated to the variable.

Definition at line 47 of file Variable.inlines.hh.

References varid.

                   {
  return varid;
}

dimension_type Parma_Polyhedra_Library::Variable::max_space_dimension ( )

inlinestatic

Returns the maximum space dimension a Variable can handle.

Definition at line 33 of file Variable.inlines.hh.

References Parma_Polyhedra_Library::not_a_dimension().

Referenced by Parma_Polyhedra_Library::max_space_dimension(), and OK().

                              {
  return not_a_dimension() - 1;
}

bool Parma_Polyhedra_Library::Variable::OK ( ) const

Checks if all the invariants are satisfied.

Definition at line 34 of file Variable.cc.

References id(), and max_space_dimension().

Referenced by Parma_Polyhedra_Library::Variables_Set::OK().

                      {
  return id() < max_space_dimension();
}

void Parma_Polyhedra_Library::Variable::set_output_function ( output_function_type * p )

inlinestatic

Sets the output function to be used for printing Variable objects.

Definition at line 67 of file Variable.inlines.hh.

References current_output_function.

                                                     {
  current_output_function = p;
}

dimension_type Parma_Polyhedra_Library::Variable::space_dimension ( ) const

inline

Returns the dimension of the vector space enclosing *this.

The returned value is id()+1.

Definition at line 52 of file Variable.inlines.hh.

References varid.

                                {
  return varid + 1;
}

memory_size_type Parma_Polyhedra_Library::Variable::total_memory_in_bytes ( ) const

inline

Returns the total size in bytes of the memory occupied by *this.

Definition at line 62 of file Variable.inlines.hh.

References external_memory_in_bytes().

                                      {
  return sizeof(*this) + external_memory_in_bytes();
}

Friends And Related Function Documentation

friend class Init

friend

Definition at line 134 of file Variable.defs.hh.

bool less	(	Variable	v,
		Variable	w
	)

Referenced by Parma_Polyhedra_Library::Variable::Compare::operator()().

bool less	(	const Variable	v,
		const Variable	w
	)

References id().

                                         {
  return v.id() < w.id();
}

std::ostream & operator<<	(	std::ostream &	s,
		const Variable	v
	)

std::ostream & operator<<	(	std::ostream &	s,
		const Variable	v
	)

                                                           {
  (*Variable::current_output_function)(s, v);
  return s;
}

std::ostream& Parma_Polyhedra_Library::IO_Operators::operator<<	(	std::ostream &	s,
		const Variable	v
	)

friend

Member Data Documentation

PPL::Variable::output_function_type * Parma_Polyhedra_Library::Variable::current_output_function = 0

staticprivate

Pointer to the current output function.

Definition at line 141 of file Variable.defs.hh.

Referenced by get_output_function(), and set_output_function().

dimension_type Parma_Polyhedra_Library::Variable::varid

private

The index of the Cartesian axis.

Definition at line 131 of file Variable.defs.hh.

Referenced by id(), and space_dimension().

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

Classes

Public Types

Public Member Functions

Static Public Member Functions

Static Private Member Functions

Private Attributes

Static Private Attributes

Friends

Related Functions

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Friends And Related Function Documentation

Member Data Documentation