NonnegativeLinearProgram Concept Reference

Definition

A model of NonnegativeLinearProgram describes a linear program of the form.

\( \newcommand{\qprel}{\gtreqless} \newcommand{\qpx}{\mathbf{x}} \newcommand{\qpl}{\mathbf{l}} \newcommand{\qpu}{\mathbf{u}} \newcommand{\qpc}{\mathbf{c}} \newcommand{\qpb}{\mathbf{b}} \newcommand{\qpy}{\mathbf{y}} \newcommand{\qpw}{\mathbf{w}} \newcommand{\qplambda}{\mathbf{\lambda}} \)

\begin{eqnarray*} \mbox{(QP)}& \mbox{minimize} &\qpc^{T}\qpx+c_0 \\ &\mbox{subject to} & A\qpx\qprel \qpb, \\ & & \qpx \geq 0 \end{eqnarray*}

in \( n\) real variables \( \qpx=(x_0,\ldots,x_{n-1})\). Here,

• \( A\) is an \( m\times n\) matrix (the constraint matrix),
• \( \qpb\) is an \( m\)-dimensional vector (the right-hand side),
• \( \qprel\) is an \( m\)-dimensional vector of relations from \( \{\leq, =, \geq\}\),
• \( \qpc\) is an \( n\)-dimensional vector (the linear objective function), and
• \( c_0\) is a constant.

The description is given by appropriate random-access iterators over the program data, see below. The program therefore comes in dense representation which includes zero entries.

Has Models:

CGAL::Quadratic_program<NT>

CGAL::Quadratic_program_from_mps<NT>

CGAL::Nonnegative_linear_program_from_iterators<A_it, B_it, R_it, FL_it, L_it, FU_it, U_it, D_it, C_it>

CGAL::Quadratic_program_from_mps<NT>

CGAL::Nonnegative_linear_program_from_iterators<A_it, B_it, R_it, C_it>

Requires:

The value types of all iterator types (nested iterator types, respectively, for A_iterator) must be convertible to some common IntegralDomain ET.

Has Models:

CGAL::Quadratic_program<NT>

See Also

QuadraticProgram

LinearProgram

NonnegativeQuadraticProgram

Types
typedef unspecified_type	A_iterator
	A random access iterator type to go columnwise over the constraint matrix \( A\). More...
typedef unspecified_type	B_iterator
	A random access iterator type to go over the entries of the right-hand side \( \qpb\).
typedef unspecified_type	R_iterator
	A random access iterator type to go over the relations \( \qprel\). More...
typedef unspecified_type	C_iterator
	A random access iterator type to go over the entries of the linear objective function vector \( c\).

Operations
int	get_n () const
	returns the number \( n\) of variables (number of columns of \( A\)) in lp.
int	get_m () const
	returns the number \( m\) of constraints (number of rows of \( A\)) in lp.
A_iterator	get_a () const
	returns an iterator over the columns of \( A\). More...
B_iterator	get_b () const
	returns an iterator over the entries of \( \qpb\). More...
R_iterator	get_r () const
	returns an iterator over the entries of \( \qprel\). More...
C_iterator	get_c () const
	returns an iterator over the entries of \( \qpc\). More...
std::iterator_traits < C_iterator >::value_type	get_c0 () const
	returns the constant term \( c_0\) of the objective function.

Member Typedef Documentation

typedef unspecified_type NonnegativeLinearProgram::A_iterator

A random access iterator type to go columnwise over the constraint matrix \( A\).

The value type is a random access iterator type for an individual column that goes over the entries in that column.

typedef unspecified_type NonnegativeLinearProgram::R_iterator

A random access iterator type to go over the relations \( \qprel\).

The value type of R_iterator is CGAL::Comparison_result.

Member Function Documentation

A_iterator NonnegativeLinearProgram::get_a

(

)

const

returns an iterator over the columns of \( A\).

The corresponding past-the-end iterator is get_a()+get_n(). For \( j=0,\ldots,n-1\), *(get_a()+j) a random access iterator for column \( j\).

B_iterator NonnegativeLinearProgram::get_b

(

)

const

returns an iterator over the entries of \( \qpb\).

The corresponding past-the-end iterator is get_b()+get_m().

C_iterator NonnegativeLinearProgram::get_c

(

)

const

returns an iterator over the entries of \( \qpc\).

The corresponding past-the-end iterator is get_c()+get_n().

R_iterator NonnegativeLinearProgram::get_r

(

)

const

returns an iterator over the entries of \( \qprel\).

The corresponding past-the-end iterator is get_r()+get_m(). The value CGAL::SMALLER stands for \( \leq\), CGAL::EQUAL stands for \( =\), and CGAL::LARGER stands for \( \geq\).