kiwi

package module
v0.0.5 Latest Latest
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 Go to latest Published: Jul 20, 2026 License: BSD-3-Clause Imports: 9 Imported by: 0

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Constants

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const (
	INVALID kind = iota
	EXTERNAL
	SLACK
	ERROR
	DUMMY
)
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const (
	OPTIONAL Strength = iota
	WEAK
	MEDIUM   = (1000 * WEAK)
	STRONG   = (1000 * MEDIUM)
	REQUIRED = (1000 * STRONG) + STRONG + MEDIUM
)
View Source 
const BadRequiredStrength = Error("Bad Required Strength")
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const EPS = 1.0e-8
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const FailedToFindLeavingRow = Error("Failed to find Leaving Row")
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const InternalSolverError = Error("Internal Solver Error")
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const SyntaxError = Error("Syntax Error")
View Source 
const UnboundedObjective = Error("Objective is Unbounded")

Variables

This section is empty.

Functions

func NearZero 

func NearZero(value float64) bool

Types

type AST 

type AST struct{ ast.Expr }

func ParseExpr 

func ParseExpr(a ...interface{}) (*AST, error)

func (AST) NewConstraint 

func (a AST) NewConstraint(vars []*Variable, options ...ConstraintOption) (*Constraint, error)

func (AST) String 

func (a AST) String() string

func (AST) TechString 

func (a AST) TechString() string

type Constrainer 

type Constrainer interface {
	EqualsConstant(float64) *Constraint
	EqualsVariable(*Variable) *Constraint
	EqualsTerm(Term) *Constraint
	EqualsExpression(Expression) *Constraint
	LessThanOrEqualsConstant(float64) *Constraint
	LessThanOrEqualsVariable(*Variable) *Constraint
	LessThanOrEqualsTerm(Term) *Constraint
	LessThanOrEqualsExpression(Expression) *Constraint
	GreaterThanOrEqualsConstant(float64) *Constraint
	GreaterThanOrEqualsVariable(*Variable) *Constraint
	GreaterThanOrEqualsTerm(Term) *Constraint
	GreaterThanOrEqualsExpression(Expression) *Constraint
}

type Constraint 

type Constraint struct {
	Expression Expression
	Operator   Operator
	Strength   Strength
}

func NewConstraint 

func NewConstraint(expr Expression, op Operator, options ...ConstraintOption) *Constraint

func ParseConstraint 

func ParseConstraint(x string, vars []*Variable, options ...ConstraintOption) (*Constraint, error)

func (*Constraint) ApplyOptions 

func (c *Constraint) ApplyOptions(options ...ConstraintOption)

func (*Constraint) String 

func (c *Constraint) String() string

type ConstraintOption 

type ConstraintOption func(*Constraint)

func WithStrength 

func WithStrength(strength Strength) ConstraintOption

WithStrength is a constraint option to set the strength of the constraint

type DuplicateConstraint 

type DuplicateConstraint struct{ *Constraint }

func (DuplicateConstraint) Error 

func (e DuplicateConstraint) Error() string

type DuplicateEditVariable 

type DuplicateEditVariable struct{ *Variable }

func (DuplicateEditVariable) Error 

func (e DuplicateEditVariable) Error() string

type DuplicateStayVariable 

type DuplicateStayVariable struct{ *Variable }

func (DuplicateStayVariable) Error 

func (e DuplicateStayVariable) Error() string

type Error 

type Error string

func EvaluationError 

func EvaluationError(a ...interface{}) Error

func (Error) Error 

func (e Error) Error() string

type Expression 

type Expression struct {
	Terms    []Term
	Constant float64
}

func (Expression) AddConstant 

func (e Expression) AddConstant(constant float64) Expression

func (Expression) AddExpression 

func (e Expression) AddExpression(other Expression) Expression

func (Expression) AddTerm 

func (e Expression) AddTerm(term Term) Expression

func (Expression) AddVariable 

func (e Expression) AddVariable(variable *Variable) Expression

func (Expression) Divide 

func (e Expression) Divide(denominator float64) Expression

func (Expression) EqualsConstant 

func (e Expression) EqualsConstant(constant float64) *Constraint

func (Expression) EqualsExpression 

func (e Expression) EqualsExpression(expression Expression) *Constraint

func (Expression) EqualsTerm 

func (e Expression) EqualsTerm(term Term) *Constraint

func (Expression) EqualsVariable 

func (e Expression) EqualsVariable(variable *Variable) *Constraint

func (Expression) GetValue 

func (e Expression) GetValue() float64

func (Expression) GreaterThanOrEqualsConstant 

func (e Expression) GreaterThanOrEqualsConstant(constant float64) *Constraint

func (Expression) GreaterThanOrEqualsExpression 

func (e Expression) GreaterThanOrEqualsExpression(expression Expression) *Constraint

func (Expression) GreaterThanOrEqualsTerm 

func (e Expression) GreaterThanOrEqualsTerm(term Term) *Constraint

func (Expression) GreaterThanOrEqualsVariable 

func (e Expression) GreaterThanOrEqualsVariable(variable *Variable) *Constraint

func (Expression) IsConstant 

func (e Expression) IsConstant() bool

func (Expression) LessThanOrEqualsConstant 

func (e Expression) LessThanOrEqualsConstant(constant float64) *Constraint

func (Expression) LessThanOrEqualsExpression 

func (e Expression) LessThanOrEqualsExpression(expression Expression) *Constraint

func (Expression) LessThanOrEqualsTerm 

func (e Expression) LessThanOrEqualsTerm(term Term) *Constraint

func (Expression) LessThanOrEqualsVariable 

func (e Expression) LessThanOrEqualsVariable(variable *Variable) *Constraint

func (Expression) Multiply 

func (e Expression) Multiply(coefficient float64) Expression

func (Expression) Negate 

func (e Expression) Negate() Expression

func (Expression) String 

func (e Expression) String() string

type Operator 

type Operator int
const (
	LE Operator = iota
	GE
	EQ
)

func (Operator) String 

func (o Operator) String() string

type Solver 

type Solver struct {
	// contains filtered or unexported fields
}

func NewSolver 

func NewSolver() *Solver

func (*Solver) AddConstraint 

func (s *Solver) AddConstraint(constraint *Constraint, options ...ConstraintOption) error

AddConstraint adds a constraint to the solver.

Returns 

DuplicateConstraint

The given constraint has already been added to the solver. 

UnsatisfiableConstraint

The given constraint is required and cannot be satisfied.

func (*Solver) AddEditVariable 

func (s *Solver) AddEditVariable(variable *Variable, options ...ConstraintOption) error

AddEditVariable adds an edit variable to the solver.

This method should be called before the `suggestValue` method is used to supply a suggested value for the given edit variable.

When no strength option is given the edit variable will be created with STRONG strength.

Returns 

DuplicateEditVariable

The given edit variable has already been added to the solver. 

BadRequiredStrength

The given strength is >= required.

func (*Solver) AddStay 

func (s *Solver) AddStay(variable *Variable, options ...ConstraintOption) error

AddStay adds a constraint that says that a particular variable shouldn’t be modified unless it needs to be - that it should “stay” as is unless there is a reason not to.

By default when no constraint option is given the strength of the stay constraint will be the weakest strength possible, which is 'OPTIONAL'.

func (*Solver) HasConstraint 

func (s *Solver) HasConstraint(constraint *Constraint) bool

HasConstraint tests whether a constraint has been added to the solver.

func (*Solver) HasEditVariable 

func (s *Solver) HasEditVariable(variable *Variable) bool

HasEditVariable tests whether an edit variable has been added to the solver.

func (*Solver) HasStay 

func (s *Solver) HasStay(variable *Variable) bool

HasStay tests whether a stay constraint has been added to the solver for the given variable.

func (*Solver) RemoveConstraint 

func (s *Solver) RemoveConstraint(constraint *Constraint) error

RemoveConstraint removes a constraint from the solver.

Returns 

UnknownConstraint

The given constraint has not been added to the solver.

func (*Solver) RemoveEditVariable 

func (s *Solver) RemoveEditVariable(variable *Variable) error

RemoveEditVariable removes an edit variable from the solver.

Returns 

UnknownEditVariable

The given edit variable has not been added to the solver.

func (*Solver) RemoveStay 

func (s *Solver) RemoveStay(variable *Variable) error

RemoveStay removes a stay constraint for the given variable from the solver.

func (*Solver) Reset 

func (s *Solver) Reset()

Reset resets the solver to the empty starting condition.

This method resets the internal solver state to the empty starting condition, as if no constraints or edit variables have been added. This can be faster than deleting the solver and creating a new one when the entire system must change, since it can avoid unecessary heap (de)allocations.

func (Solver) String 

func (s Solver) String() string

func (*Solver) SuggestValue 

func (s *Solver) SuggestValue(variable *Variable, value float64) error

SuggestValue suggests a value for the given edit variable.

This method should be used after an edit variable as been added to the solver in order to suggest the value for that variable. After all suggestions have been made, the `solve` method can be used to update the values of all variables.

Returns 

UnknownEditVariable

The given edit variable has not been added to the solver.

func (*Solver) UpdateStays 

func (s *Solver) UpdateStays()

UpdateStays updates all stay constraints to match the value their associated variable currently holds.

This is automatically called by RemoveEditVariable to commit the changes caused by the editing of the variable.

func (*Solver) UpdateVariables 

func (s *Solver) UpdateVariables()

UpdateVariables updates the values of the external solver variables.

type Strength 

type Strength float64

func Medium 

func Medium(weight ...float64) Strength

Medium returns a medium strength with a weight in the range [1 .. 1000)

func Strong 

func Strong(weight ...float64) Strength

Strong returns a strong strength with a weight in the range [1 .. 1000)

func Weak 

func Weak(weight ...float64) Strength

Weak returns a weak strength with a weight in the range [1 .. 1000)

func (Strength) Base 

func (s Strength) Base() Strength

func (Strength) String 

func (s Strength) String() string

func (Strength) WithWeight 

func (s Strength) WithWeight(weight float64) Strength

type Term 

type Term struct {
	Variable    *Variable
	Coefficient float64
}

func (Term) AddConstant 

func (t Term) AddConstant(constant float64) Expression

func (Term) AddExpression 

func (t Term) AddExpression(expression Expression) Expression

func (Term) AddTerm 

func (t Term) AddTerm(term Term) Expression

func (Term) AddVariable 

func (t Term) AddVariable(variable *Variable) Expression

func (Term) Divide 

func (t Term) Divide(denominator float64) Term

func (Term) EqualsConstant 

func (t Term) EqualsConstant(constant float64) *Constraint

func (Term) EqualsExpression 

func (t Term) EqualsExpression(expression Expression) *Constraint

func (Term) EqualsTerm 

func (t Term) EqualsTerm(term Term) *Constraint

func (Term) EqualsVariable 

func (t Term) EqualsVariable(variable *Variable) *Constraint

func (Term) GetValue 

func (t Term) GetValue() float64

func (Term) GreaterThanOrEqualsConstant 

func (t Term) GreaterThanOrEqualsConstant(constant float64) *Constraint

func (Term) GreaterThanOrEqualsExpression 

func (t Term) GreaterThanOrEqualsExpression(expression Expression) *Constraint

func (Term) GreaterThanOrEqualsTerm 

func (t Term) GreaterThanOrEqualsTerm(term Term) *Constraint

func (Term) GreaterThanOrEqualsVariable 

func (t Term) GreaterThanOrEqualsVariable(variable *Variable) *Constraint

func (Term) LessThanOrEqualsConstant 

func (t Term) LessThanOrEqualsConstant(constant float64) *Constraint

func (Term) LessThanOrEqualsExpression 

func (t Term) LessThanOrEqualsExpression(expression Expression) *Constraint

func (Term) LessThanOrEqualsTerm 

func (t Term) LessThanOrEqualsTerm(term Term) *Constraint

func (Term) LessThanOrEqualsVariable 

func (t Term) LessThanOrEqualsVariable(variable *Variable) *Constraint

func (Term) Multiply 

func (t Term) Multiply(coefficient float64) Term

func (Term) Negate 

func (t Term) Negate() Term

func (Term) String 

func (t Term) String() string

type UnknownConstraint 

type UnknownConstraint struct{ *Constraint }

func (UnknownConstraint) Error 

func (e UnknownConstraint) Error() string

type UnknownEditVariable 

type UnknownEditVariable struct{ *Variable }

func (UnknownEditVariable) Error 

func (e UnknownEditVariable) Error() string

type UnknownStayVariable 

type UnknownStayVariable struct{ *Variable }

func (UnknownStayVariable) Error 

func (e UnknownStayVariable) Error() string

type UnknownVariableName 

type UnknownVariableName struct{ Name string }

func (UnknownVariableName) Error 

func (e UnknownVariableName) Error() string

type UnsatisfiableConstraint 

type UnsatisfiableConstraint struct{ *Constraint }

func (UnsatisfiableConstraint) Error 

func (e UnsatisfiableConstraint) Error() string

type Variable 

type Variable struct {
	Name  string
	Value float64
}

func NewVariable 

func NewVariable(name string) *Variable

func Var 

func Var(n string, v ...float64) *Variable

func Vars 

func Vars(names ...string) []*Variable

func (*Variable) AddConstant 

func (v *Variable) AddConstant(constant float64) Expression

func (*Variable) AddExpression 

func (v *Variable) AddExpression(expression Expression) Expression

func (*Variable) AddTerm 

func (v *Variable) AddTerm(term Term) Expression

func (*Variable) AddVariable 

func (v *Variable) AddVariable(variable *Variable) Expression

func (*Variable) Divide 

func (v *Variable) Divide(denominator float64) Term

func (*Variable) EqualsConstant 

func (v *Variable) EqualsConstant(constant float64) *Constraint

func (*Variable) EqualsExpression 

func (v *Variable) EqualsExpression(expression Expression) *Constraint

func (*Variable) EqualsTerm 

func (v *Variable) EqualsTerm(term Term) *Constraint

func (*Variable) EqualsVariable 

func (v *Variable) EqualsVariable(variable *Variable) *Constraint

func (*Variable) GreaterThanOrEqualsConstant 

func (v *Variable) GreaterThanOrEqualsConstant(constant float64) *Constraint

func (*Variable) GreaterThanOrEqualsExpression 

func (v *Variable) GreaterThanOrEqualsExpression(expression Expression) *Constraint

func (*Variable) GreaterThanOrEqualsTerm 

func (v *Variable) GreaterThanOrEqualsTerm(term Term) *Constraint

func (*Variable) GreaterThanOrEqualsVariable 

func (v *Variable) GreaterThanOrEqualsVariable(variable *Variable) *Constraint

func (*Variable) LessThanOrEqualsConstant 

func (v *Variable) LessThanOrEqualsConstant(constant float64) *Constraint

func (*Variable) LessThanOrEqualsExpression 

func (v *Variable) LessThanOrEqualsExpression(expression Expression) *Constraint

func (*Variable) LessThanOrEqualsTerm 

func (v *Variable) LessThanOrEqualsTerm(term Term) *Constraint

func (*Variable) LessThanOrEqualsVariable 

func (v *Variable) LessThanOrEqualsVariable(variable *Variable) *Constraint

func (*Variable) Multiply 

func (v *Variable) Multiply(coefficient float64) Term

func (*Variable) Negate 

func (v *Variable) Negate() Term

func (*Variable) String 

func (v *Variable) String() string

Source Files

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Directories

Path Synopsis
gio module

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