doubleton_action Class Reference

Solve ax+by=c for y and substitute y out of the problem. More...

#include <CoinPresolveDoubleton.hpp>

Inheritance diagram for doubleton_action:
CoinPresolveAction

List of all members.

Classes

struct  action

Public Member Functions

const char * name () const
 A name for debug printing.
void postsolve (CoinPostsolveMatrix *prob) const
 Apply the postsolve transformation for this particular presolve action.
virtual ~doubleton_action ()

Static Public Member Functions

static const CoinPresolveActionpresolve (CoinPresolveMatrix *, const CoinPresolveAction *next)

Public Attributes

const int nactions_
const action *const actions_

Detailed Description

Solve ax+by=c for y and substitute y out of the problem.

This moves the bounds information for y onto x, making y free and allowing us to substitute it away.

	   a x + b y = c
	   l1 <= x <= u1
	   l2 <= y <= u2	==>
	  
	   l2 <= (c - a x) / b <= u2
	   b/-a > 0 ==> (b l2 - c) / -a <= x <= (b u2 - c) / -a
	   b/-a < 0 ==> (b u2 - c) / -a <= x <= (b l2 - c) / -a
  

Definition at line 26 of file CoinPresolveDoubleton.hpp.


Constructor & Destructor Documentation

virtual doubleton_action::~doubleton_action (  )  [virtual]

Member Function Documentation

const char* doubleton_action::name (  )  const [inline, virtual]

A name for debug printing.

It is expected that the name is not stored in the transform itself.

Implements CoinPresolveAction.

Definition at line 62 of file CoinPresolveDoubleton.hpp.

static const CoinPresolveAction* doubleton_action::presolve ( CoinPresolveMatrix ,
const CoinPresolveAction next 
) [static]
void doubleton_action::postsolve ( CoinPostsolveMatrix prob  )  const [virtual]

Apply the postsolve transformation for this particular presolve action.

Implements CoinPresolveAction.


Member Data Documentation

Definition at line 50 of file CoinPresolveDoubleton.hpp.

Definition at line 51 of file CoinPresolveDoubleton.hpp.


The documentation for this class was generated from the following file:
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Defines

Generated on 28 Aug 2016 for CoinUtils by  doxygen 1.6.1