Detailed Description

The violation of an int_mod constraint is defined as follow:

if target and expr0 have the same sign: min( abs(value(target) - (value(expr0) % value(expr1))), abs(value(target)) + abs((value(expr0) % value(expr1)) - value(expr1)), abs(value(expr0) % value(expr1)) + abs(value(target) - value(expr1)), )

if target and expr0 have different sign: abs(target) + abs(expr0)

Note: the modulo (expr1) is always fixed.

Definition at line 525 of file constraint_violation.h.

#include <constraint_violation.h>

Inheritance diagram for operations_research::sat::CompiledIntModConstraint:

Public Member Functions
	CompiledIntModConstraint (const ConstraintProto &ct_proto)
	--— CompiledIntModConstraint --—
	~CompiledIntModConstraint () override=default
int64_t	ComputeViolation (absl::Span< const int64_t > solution) override
Public Member Functions inherited from operations_research::sat::CompiledConstraintWithProto
	CompiledConstraintWithProto (const ConstraintProto &ct_proto)
	--— CompiledConstraintWithProto --—
	~CompiledConstraintWithProto () override=default
const ConstraintProto &	ct_proto () const
std::vector< int >	UsedVariables (const CpModelProto &model_proto) const final
	This just returns the variables used by the stored ct_proto_.
Public Member Functions inherited from operations_research::sat::CompiledConstraint
	CompiledConstraint ()=default
virtual	~CompiledConstraint ()=default
void	InitializeViolation (absl::Span< const int64_t > solution)
	Recomputes the violation of the constraint from scratch.
virtual void	PerformMove (int var, int64_t old_value, absl::Span< const int64_t > solution_with_new_value)
	Updates the violation with the new value.
virtual int64_t	ViolationDelta (int var, int64_t old_value, absl::Span< const int64_t > solution_with_new_value)
	Returns the delta if var changes from old_value to solution[var].
int64_t	violation () const
	The cached violation of this constraint.

Additional Inherited Members
Protected Attributes inherited from operations_research::sat::CompiledConstraint
int64_t	violation_

Constructor & Destructor Documentation

◆ CompiledIntModConstraint()

operations_research::sat::CompiledIntModConstraint::CompiledIntModConstraint ( const ConstraintProto & ct_proto )

explicit

--— CompiledIntModConstraint --—

Definition at line 1033 of file constraint_violation.cc.

◆ ~CompiledIntModConstraint()

operations_research::sat::CompiledIntModConstraint::~CompiledIntModConstraint ( )

overridedefault

Member Function Documentation

◆ ComputeViolation()

int64_t operations_research::sat::CompiledIntModConstraint::ComputeViolation ( absl::Span< const int64_t > solution )

overridevirtual

Computes the violation of a constraint.

This is called by InitializeViolation() and also the default implementation of ViolationDelta().

Note: The violation computation assumes the modulo is constant.

Easy case.

Different signs. We use the sum of the absolute value to have a better gradient. We could also use the min of target_move and the expr_move.

Implements operations_research::sat::CompiledConstraint.

Definition at line 1037 of file constraint_violation.cc.

The documentation for this class was generated from the following files:

ortools/sat/constraint_violation.h
ortools/sat/constraint_violation.cc