Parma_Polyhedra_Library::Box_Helpers Class Reference

#include <Box_defs.hh>

Static Public Member Functions
static bool	extract_interval_congruence (const Congruence &cg, dimension_type &cg_num_vars, dimension_type &cg_only_var)

Related Functions
(Note that these are not member functions.)
static bool	extract_interval_constraint (const Constraint &c, dimension_type &c_num_vars, dimension_type &c_only_var)
	Decodes the constraint c as an interval constraint. More...

Detailed Description

Definition at line 2245 of file Box_defs.hh.

Member Function Documentation

bool Parma_Polyhedra_Library::Box_Helpers::extract_interval_congruence ( const Congruence &  cg, dimension_type &  cg_num_vars, dimension_type &  cg_only_var  )

static

Definition at line 48 of file Box.cc.

References Parma_Polyhedra_Library::Expression_Adapter< T >::all_zeroes(), Parma_Polyhedra_Library::Congruence::expression(), Parma_Polyhedra_Library::Expression_Adapter< T >::first_nonzero(), Parma_Polyhedra_Library::Congruence::is_equality(), and Parma_Polyhedra_Library::Congruence::space_dimension().

Referenced by Parma_Polyhedra_Library::Box< ITV >::add_congruence_no_check().

                                                                           {
  // Check for preconditions.
  PPL_ASSERT(cg_num_vars == 0 && cg_only_var == 0);
  // Only equality congruences can be intervals.
  PPL_ASSERT(cg.is_equality());

  cg_only_var = cg.expression().first_nonzero(1, cg.space_dimension() + 1);
  if (cg_only_var == cg.space_dimension() + 1) {
    // All the inhomogeneous coefficients are zero.
    return true;
  }

  ++cg_num_vars;
  --cg_only_var;
  return cg.expression().all_zeroes(cg_only_var + 2, cg.space_dimension() + 1);
}

Friends And Related Function Documentation

bool Parma_Polyhedra_Library::Box_Helpers::extract_interval_constraint ( const Constraint &  c, dimension_type &  c_num_vars, dimension_type &  c_only_var  )

related

Decodes the constraint c as an interval constraint.

Returns

true if the constraint c is an interval constraint; false otherwise.

Parameters

c	The constraint to be decoded.
c_num_vars	If true is returned, then it will be set to the number of variables having a non-zero coefficient. The only legal values will therefore be 0 and 1.
c_only_var	If true is returned and if c_num_vars is not set to 0, then it will be set to the index of the only variable having a non-zero coefficient in c.

Definition at line 30 of file Box.cc.

References Parma_Polyhedra_Library::Expression_Hide_Last< T >::all_zeroes(), Parma_Polyhedra_Library::Constraint::expression(), Parma_Polyhedra_Library::Expression_Hide_Last< T >::first_nonzero(), and Parma_Polyhedra_Library::Constraint::space_dimension().

Referenced by Parma_Polyhedra_Library::Box< ITV >::add_constraint_no_check(), Parma_Polyhedra_Library::Box< ITV >::get_limiting_box(), Parma_Polyhedra_Library::Box< ITV >::refine_no_check(), Parma_Polyhedra_Library::Box< ITV >::relation_with(), and Parma_Polyhedra_Library::Box< ITV >::wrap_assign().

                                                                          {
  // Check for preconditions.
  PPL_ASSERT(c_num_vars == 0 && c_only_var == 0);

  c_only_var = c.expression().first_nonzero(1, c.space_dimension() + 1);
  if (c_only_var == c.space_dimension() + 1) {
    // All the inhomogeneous coefficients are zero.
    return true;
  }

  ++c_num_vars;
  --c_only_var;
  return c.expression().all_zeroes(c_only_var + 2, c.space_dimension() + 1);
}

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

• Box_defs.hh
• Box.cc