Inherits Parma_Polyhedra_Library::Linear_Row.
Public Types | |
enum | Type { EQUALITY, NONSTRICT_INEQUALITY, STRICT_INEQUALITY } |
The constraint type. More... | |
Public Member Functions | |
Constraint (const Constraint &c) | |
Ordinary copy-constructor. | |
~Constraint () | |
Destructor. | |
Constraint & | operator= (const Constraint &c) |
Assignment operator. | |
dimension_type | space_dimension () const |
Returns the dimension of the vector space enclosing *this . | |
Type | type () const |
Returns the constraint type of *this . | |
bool | is_equality () const |
Returns true if and only if *this is an equality constraint. | |
bool | is_inequality () const |
Returns true if and only if *this is an inequality constraint (either strict or non-strict). | |
bool | is_nonstrict_inequality () const |
Returns true if and only if *this is a non-strict inequality constraint. | |
bool | is_strict_inequality () const |
Returns true if and only if *this is a strict inequality constraint. | |
Coefficient_traits::const_reference | coefficient (Variable v) const |
Returns the coefficient of v in *this . | |
Coefficient_traits::const_reference | inhomogeneous_term () const |
Returns the inhomogeneous term of *this . | |
memory_size_type | total_memory_in_bytes () const |
Returns a lower bound to 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 | is_tautological () const |
Returns true if and only if *this is a tautology (i.e., an always true constraint). | |
bool | is_inconsistent () const |
Returns true if and only if *this is inconsistent (i.e., an always false constraint). | |
bool | is_equivalent_to (const Constraint &y) const |
Returns true if and only if *this and y are equivalent constraints. | |
bool | OK () const |
Checks if all the invariants are satisfied. | |
void | swap (Constraint &y) |
Swaps *this with y . | |
Static Public Member Functions | |
static dimension_type | max_space_dimension () |
Returns the maximum space dimension a Constraint can handle. | |
static const Constraint & | zero_dim_false () |
The unsatisfiable (zero-dimension space) constraint ![]() | |
static const Constraint & | zero_dim_positivity () |
The true (zero-dimension space) constraint ![]() | |
Friends | |
Constraint | operator== (const Linear_Expression &e1, const Linear_Expression &e2) |
Returns the constraint e1 = e2 . | |
Constraint | operator== (const Linear_Expression &e, Coefficient_traits::const_reference n) |
Returns the constraint e = n . | |
Constraint | operator== (Coefficient_traits::const_reference n, const Linear_Expression &e) |
Returns the constraint n = e . | |
Constraint | operator>= (const Linear_Expression &e1, const Linear_Expression &e2) |
Returns the constraint e1 >= e2 . | |
Constraint | operator>= (const Linear_Expression &e, Coefficient_traits::const_reference n) |
Returns the constraint e >= n . | |
Constraint | operator>= (Coefficient_traits::const_reference n, const Linear_Expression &e) |
Returns the constraint n >= e . | |
Constraint | operator<= (const Linear_Expression &e1, const Linear_Expression &e2) |
Returns the constraint e1 <= e2 . | |
Constraint | operator<= (const Linear_Expression &e, Coefficient_traits::const_reference n) |
Returns the constraint e <= n . | |
Constraint | operator<= (Coefficient_traits::const_reference n, const Linear_Expression &e) |
Returns the constraint n <= e . | |
Constraint | operator> (const Linear_Expression &e1, const Linear_Expression &e2) |
Returns the constraint e1 > e2 . | |
Constraint | operator> (const Linear_Expression &e, Coefficient_traits::const_reference n) |
Returns the constraint e > n . | |
Constraint | operator> (Coefficient_traits::const_reference n, const Linear_Expression &e) |
Returns the constraint n > e . | |
Constraint | operator< (const Linear_Expression &e1, const Linear_Expression &e2) |
Returns the constraint e1 < e2 . | |
Constraint | operator< (const Linear_Expression &e, Coefficient_traits::const_reference n) |
Returns the constraint e < n . | |
Constraint | operator< (Coefficient_traits::const_reference n, const Linear_Expression &e) |
Returns the constraint n < e . | |
Related Functions | |
(Note that these are not member functions.) | |
bool | operator== (const Constraint &x, const Constraint &y) |
Returns true if and only if x is equivalent to y . | |
bool | operator!= (const Constraint &x, const Constraint &y) |
Returns true if and only if x is not equivalent to y . | |
void | swap (Parma_Polyhedra_Library::Constraint &x, Parma_Polyhedra_Library::Constraint &y) |
Specializes std::swap . | |
std::ostream & | operator<< (std::ostream &s, const Constraint &c) |
Output operator. | |
std::ostream & | operator<< (std::ostream &s, const Constraint::Type &t) |
Output operator. |
An object of the class Constraint is either:
where is the dimension of the space,
is the integer coefficient of variable
and
is the integer inhomogeneous term.
==
), non-strict inequalities (>=
and <=
) and strict inequalities (<
and >
). The space dimension of a constraint is defined as the maximum space dimension of the arguments of its constructor.x
, y
and z
are defined as follows: Variable x(0); Variable y(1); Variable z(2);
Constraint eq_c(3*x + 5*y - z == 0);
Constraint ineq_c(4*x >= 2*y - 13);
Constraint strict_ineq_c(4*x > 2*y - 13);
Constraint false_c = Constraint::zero_dim_false();
Constraint false_c1(Linear_Expression::zero() == 1); Constraint false_c2(Linear_Expression::zero() >= 1); Constraint false_c3(Linear_Expression::zero() > 0);
Constraint false_c(0*z == 1);
Constraint c1(x - 5*y + 3*z <= 4); cout << "Constraint c1: " << c1 << endl; if (c1.is_equality()) cout << "Constraint c1 is not an inequality." << endl; else { Linear_Expression e; for (int i = c1.space_dimension() - 1; i >= 0; i--) e += c1.coefficient(Variable(i)) * Variable(i); e += c1.inhomogeneous_term(); Constraint c2 = c1.is_strict_inequality() ? (e <= 0) : (e < 0); cout << "Complement c2: " << c2 << endl; }
Constraint c1: -A + 5*B - 3*C >= -4 Complement c2: A - 5*B + 3*C > 4
Coefficient_traits::const_reference Parma_Polyhedra_Library::Constraint::coefficient | ( | Variable | v | ) | const [inline] |
Returns the coefficient of v
in *this
.
std::invalid_argument | thrown if the index of v is greater than or equal to the space dimension of *this . |
bool Parma_Polyhedra_Library::Constraint::is_tautological | ( | ) | const |
Returns true
if and only if *this
is a tautology (i.e., an always true constraint).
A tautology can have either one of the following forms:
bool Parma_Polyhedra_Library::Constraint::is_inconsistent | ( | ) | const |
Returns true
if and only if *this
is inconsistent (i.e., an always false constraint).
An inconsistent constraint can have either one of the following forms:
bool Parma_Polyhedra_Library::Constraint::is_equivalent_to | ( | const Constraint & | y | ) | const |
Returns true
if and only if *this
and y
are equivalent constraints.
Constraints having different space dimensions are not equivalent. Note that constraints having different types may nonetheless be equivalent, if they both are tautologies or inconsistent.
Constraint operator== | ( | const Linear_Expression & | e1, | |
const Linear_Expression & | e2 | |||
) | [friend] |
Returns the constraint e1
= e2
.
Constraint operator== | ( | const Linear_Expression & | e, | |
Coefficient_traits::const_reference | n | |||
) | [friend] |
Returns the constraint e
= n
.
Constraint operator== | ( | Coefficient_traits::const_reference | n, | |
const Linear_Expression & | e | |||
) | [friend] |
Returns the constraint n
= e
.
Constraint operator>= | ( | const Linear_Expression & | e1, | |
const Linear_Expression & | e2 | |||
) | [friend] |
Returns the constraint e1
>= e2
.
Constraint operator>= | ( | const Linear_Expression & | e, | |
Coefficient_traits::const_reference | n | |||
) | [friend] |
Returns the constraint e
>= n
.
Constraint operator>= | ( | Coefficient_traits::const_reference | n, | |
const Linear_Expression & | e | |||
) | [friend] |
Returns the constraint n
>= e
.
Constraint operator<= | ( | const Linear_Expression & | e1, | |
const Linear_Expression & | e2 | |||
) | [friend] |
Returns the constraint e1
<= e2
.
Constraint operator<= | ( | const Linear_Expression & | e, | |
Coefficient_traits::const_reference | n | |||
) | [friend] |
Returns the constraint e
<= n
.
Constraint operator<= | ( | Coefficient_traits::const_reference | n, | |
const Linear_Expression & | e | |||
) | [friend] |
Returns the constraint n
<= e
.
Constraint operator> | ( | const Linear_Expression & | e1, | |
const Linear_Expression & | e2 | |||
) | [friend] |
Returns the constraint e1
> e2
.
Constraint operator> | ( | const Linear_Expression & | e, | |
Coefficient_traits::const_reference | n | |||
) | [friend] |
Returns the constraint e
> n
.
Constraint operator> | ( | Coefficient_traits::const_reference | n, | |
const Linear_Expression & | e | |||
) | [friend] |
Returns the constraint n
> e
.
Constraint operator< | ( | const Linear_Expression & | e1, | |
const Linear_Expression & | e2 | |||
) | [friend] |
Returns the constraint e1
< e2
.
Constraint operator< | ( | const Linear_Expression & | e, | |
Coefficient_traits::const_reference | n | |||
) | [friend] |
Returns the constraint e
< n
.
Constraint operator< | ( | Coefficient_traits::const_reference | n, | |
const Linear_Expression & | e | |||
) | [friend] |
Returns the constraint n
< e
.
bool operator== | ( | const Constraint & | x, | |
const Constraint & | y | |||
) | [related] |
Returns true
if and only if x
is equivalent to y
.
bool operator!= | ( | const Constraint & | x, | |
const Constraint & | y | |||
) | [related] |
Returns true
if and only if x
is not equivalent to y
.
void swap | ( | Parma_Polyhedra_Library::Constraint & | x, | |
Parma_Polyhedra_Library::Constraint & | y | |||
) | [related] |
Specializes std::swap
.
std::ostream & operator<< | ( | std::ostream & | s, | |
const Constraint & | c | |||
) | [related] |
Output operator.
std::ostream & operator<< | ( | std::ostream & | s, | |
const Constraint::Type & | t | |||
) | [related] |
Output operator.