org.apache.commons.math.optimization.linear

Class LinearConstraint

java.lang.Object

org.apache.commons.math.optimization.linear.LinearConstraint

All Implemented Interfaces:

Serializable

public class LinearConstraint
extends Object
implements Serializable

A linear constraint for a linear optimization problem.

A linear constraint has one of the forms:

• c₁x₁ + ... c_nx_n = v
• c₁x₁ + ... c_nx_n <= v
• c₁x₁ + ... c_nx_n >= v
• l₁x₁ + ... l_nx_n + l_cst = r₁x₁ + ... r_nx_n + r_cst
• l₁x₁ + ... l_nx_n + l_cst <= r₁x₁ + ... r_nx_n + r_cst
• l₁x₁ + ... l_nx_n + l_cst >= r₁x₁ + ... r_nx_n + r_cst

The c_i, l_i or r_i are the coefficients of the constraints, the x_i are the coordinates of the current point and v is the value of the constraint.

Since:

2.0

Version:

$Revision: 922713 $ $Date: 2010-03-14 02:26:13 +0100 (dim. 14 mars 2010) $

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private RealVector	coefficients Coefficients of the constraint (left hand side).
private Relationship	relationship Relationship between left and right hand sides (=, <=, >=).
private static long	serialVersionUID Serializable version identifier.
private double	value Value of the constraint (right hand side).

Constructor Summary

Constructors

Constructor and Description
LinearConstraint(double[] lhsCoefficients, double lhsConstant, Relationship relationship, double[] rhsCoefficients, double rhsConstant) Build a constraint involving two linear equations.
LinearConstraint(double[] coefficients, Relationship relationship, double value) Build a constraint involving a single linear equation.
LinearConstraint(RealVector lhsCoefficients, double lhsConstant, Relationship relationship, RealVector rhsCoefficients, double rhsConstant) Build a constraint involving two linear equations.
LinearConstraint(RealVector coefficients, Relationship relationship, double value) Build a constraint involving a single linear equation.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object other)
RealVector	getCoefficients() Get the coefficients of the constraint (left hand side).
Relationship	getRelationship() Get the relationship between left and right hand sides.
double	getValue() Get the value of the constraint (right hand side).
int	hashCode()
private void	readObject(ObjectInputStream ois) Deserialize the instance.
private void	writeObject(ObjectOutputStream oos) Serialize the instance.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Field Detail

serialVersionUID

private static final long serialVersionUID

Serializable version identifier.

See Also:

Constant Field Values

coefficients

private final transient RealVector coefficients

Coefficients of the constraint (left hand side).

relationship

private final Relationship relationship

Relationship between left and right hand sides (=, <=, >=).

value

private final double value

Value of the constraint (right hand side).

Constructor Detail

LinearConstraint

public LinearConstraint(double[] coefficients,
                Relationship relationship,
                double value)

Build a constraint involving a single linear equation.

A linear constraint with a single linear equation has one of the forms:

• c₁x₁ + ... c_nx_n = v
• c₁x₁ + ... c_nx_n <= v
• c₁x₁ + ... c_nx_n >= v

Parameters:

coefficients - The coefficients of the constraint (left hand side)

relationship - The type of (in)equality used in the constraint

value - The value of the constraint (right hand side)

LinearConstraint

public LinearConstraint(RealVector coefficients,
                Relationship relationship,
                double value)

Build a constraint involving a single linear equation.

A linear constraint with a single linear equation has one of the forms:

• c₁x₁ + ... c_nx_n = v
• c₁x₁ + ... c_nx_n <= v
• c₁x₁ + ... c_nx_n >= v

Parameters:

coefficients - The coefficients of the constraint (left hand side)

relationship - The type of (in)equality used in the constraint

value - The value of the constraint (right hand side)

LinearConstraint

public LinearConstraint(double[] lhsCoefficients,
                double lhsConstant,
                Relationship relationship,
                double[] rhsCoefficients,
                double rhsConstant)

Build a constraint involving two linear equations.

A linear constraint with two linear equation has one of the forms:

• l₁x₁ + ... l_nx_n + l_cst = r₁x₁ + ... r_nx_n + r_cst
• l₁x₁ + ... l_nx_n + l_cst <= r₁x₁ + ... r_nx_n + r_cst
• l₁x₁ + ... l_nx_n + l_cst >= r₁x₁ + ... r_nx_n + r_cst

Parameters:

lhsCoefficients - The coefficients of the linear expression on the left hand side of the constraint

lhsConstant - The constant term of the linear expression on the left hand side of the constraint

relationship - The type of (in)equality used in the constraint

rhsCoefficients - The coefficients of the linear expression on the right hand side of the constraint

rhsConstant - The constant term of the linear expression on the right hand side of the constraint

LinearConstraint

public LinearConstraint(RealVector lhsCoefficients,
                double lhsConstant,
                Relationship relationship,
                RealVector rhsCoefficients,
                double rhsConstant)

Build a constraint involving two linear equations.

A linear constraint with two linear equation has one of the forms:

• l₁x₁ + ... l_nx_n + l_cst = r₁x₁ + ... r_nx_n + r_cst
• l₁x₁ + ... l_nx_n + l_cst <= r₁x₁ + ... r_nx_n + r_cst
• l₁x₁ + ... l_nx_n + l_cst >= r₁x₁ + ... r_nx_n + r_cst

Parameters:

lhsCoefficients - The coefficients of the linear expression on the left hand side of the constraint

lhsConstant - The constant term of the linear expression on the left hand side of the constraint

relationship - The type of (in)equality used in the constraint

rhsCoefficients - The coefficients of the linear expression on the right hand side of the constraint

rhsConstant - The constant term of the linear expression on the right hand side of the constraint

Method Detail

getCoefficients

public RealVector getCoefficients()

Get the coefficients of the constraint (left hand side).

Returns:

coefficients of the constraint (left hand side)

getRelationship

public Relationship getRelationship()

Get the relationship between left and right hand sides.

Returns:

relationship between left and right hand sides

getValue

public double getValue()

Get the value of the constraint (right hand side).

Returns:

value of the constraint (right hand side)

equals

public boolean equals(Object other)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

writeObject

private void writeObject(ObjectOutputStream oos)
                  throws IOException

Serialize the instance.

Parameters:

oos - stream where object should be written

Throws:

IOException - if object cannot be written to stream

readObject

private void readObject(ObjectInputStream ois)
                 throws ClassNotFoundException,
                        IOException

Deserialize the instance.

Parameters:

ois - stream from which the object should be read

Throws:

ClassNotFoundException - if a class in the stream cannot be found

IOException - if object cannot be read from the stream