Documentation
¶
Overview ¶
Package lp provides foundational types and utilities for defining and manipulating linear programming (LP) models.
It defines core abstractions such as variables, expressions, constraints, objective functions, and problem categories (e.g., continuous, integer).
The package supports constructing LP problems programmatically using types like LinearProgram, LpVariable, LpTerm, and LpExpression.
Example usage:
vars := []lp.LpVariable{
lp.NewVariable("x1"),
lp.NewVariable("x2"),
}
prog := lp.NewLinearProgram("Example LP", vars)
Index ¶
- Constants
- Variables
- type LinearProgram
- func (prog *LinearProgram) AddConstraint(constraint LpExpression, constraintType LpConstraintType, ...)
- func (prog *LinearProgram) AddIPConstraints()
- func (prog *LinearProgram) AddObjective(sense LpSense, objective LpExpression)
- func (lp *LinearProgram) PrintSolution()
- func (lp *LinearProgram) String() string
- type LpCategory
- type LpConstraintType
- type LpExpression
- type LpSense
- type LpStatus
- type LpTerm
- type LpVariable
Constants ¶
const ( LpMinimise = LpSense(-1) LpMaximise = LpSense(1) )
Variables ¶
var LpStatusMap = map[LpStatus]string{ LpStatusNotSolved: "Not Solved", LpStatusOptimal: "Optimal", LpStatusInfeasible: "Infeasible", LpStatusUnbounded: "Unbounded", LpStatusUndefined: "Undefined", LpStatusNotImplemented: "Not Implemented", }
LpStatusMap maps LpStatus values to their string representations.
Functions ¶
This section is empty.
Types ¶
type LinearProgram ¶
type LinearProgram struct {
// Solution
Solution float64 // z
// Matrix Representation
Variables *mat.VecDense // x
ObjectiveFunc *mat.VecDense // c
Constraints *mat.Dense // A
RHS *mat.VecDense // b
// Simplex Internal Variables
Indices *mat.VecDense // Indices of basic variables
// Others
Description string
VariablesMap []LpVariable
Status LpStatus
Sense LpSense
ConstraintVector []LpConstraintType
// contains filtered or unexported fields
}
LinearProgram represents a linear programming problem in standard form.
func NewLinearProgram ¶
func NewLinearProgram(desc string, vars []LpVariable) LinearProgram
NewLinearProgram Create a new Linear Program
func (*LinearProgram) AddConstraint ¶
func (prog *LinearProgram) AddConstraint(constraint LpExpression, constraintType LpConstraintType, rightHandSide float64)
AddConstraint Add a constraint to the linear program
func (*LinearProgram) AddIPConstraints ¶
func (prog *LinearProgram) AddIPConstraints()
AddIPConstraints adds integer programming constraints to the linear program.
func (*LinearProgram) AddObjective ¶
func (prog *LinearProgram) AddObjective(sense LpSense, objective LpExpression)
AddObjective Add an objective to the linear program
func (*LinearProgram) PrintSolution ¶
func (lp *LinearProgram) PrintSolution()
PrintSolution prints the solution of the linear program in a human-readable format.
func (*LinearProgram) String ¶
func (lp *LinearProgram) String() string
String returns a string representation of the LinearProgram String returns a string representation of the LinearProgram.
type LpCategory ¶
type LpCategory int
LpCategory represents the category of a linear programming variable, such as continuous, integer, or binary.
const ( LpCategoryContinuous LpCategory = iota LpCategoryInteger LpCategoryBinary )
type LpConstraintType ¶
type LpConstraintType int
LpConstraintType represents the type of a constraint in a linear programming problem.
const ( LpConstraintLE LpConstraintType = -1 LpConstraintEQ LpConstraintType = 0 LpConstraintGE LpConstraintType = 1 )
type LpExpression ¶
type LpExpression struct {
Terms []LpTerm
}
LpExpression represents the LHS of a linear expression
func NewExpression ¶
func NewExpression(terms []LpTerm) LpExpression
NewExpression creates a new LpExpression with the given terms
type LpSense ¶
type LpSense int
LpSense represents the sense of the linear programming problem, either minimization or maximization.
type LpStatus ¶
type LpStatus int
LpStatus represents the current status of solving the linear programming problem.
type LpTerm ¶
type LpTerm struct {
Coefficient float64
Variable LpVariable // These get added to the variable list in the LinearProgram??
}
LpTerm represents a term in a linear expression, consisting of a coefficient and a variable.
func NewTerm ¶
func NewTerm(coefficient float64, variable LpVariable) LpTerm
NewTerm creates a new LpTerm with the given coefficient and variable.
type LpVariable ¶
type LpVariable struct {
Name string
Value float64
IsSlack bool
IsArtificial bool
Category LpCategory
}
LpVariable represents a variable in a linear programming problem.
func NewVariable ¶
func NewVariable(name string, category ...LpCategory) LpVariable
NewVariable creates a new LpVariable with the given name.
Source Files