BCP_warmstart_basis Class Reference

#include <BCP_warmstart_basis.hpp>

Inheritance diagram for BCP_warmstart_basis:

List of all members.

Public Member Functions
virtual CoinWarmStart *	convert_to_CoinWarmStart () const
virtual BCP_storage_t	storage () const
virtual BCP_warmstart *	clone () const
virtual BCP_warmstart *	empty_wrt_this () const
virtual int	storage_size () const
virtual void	update (const BCP_warmstart *const change)
virtual BCP_warmstart *	as_change (const BCP_warmstart *const old_ws, const BCP_vec< int > &del_vars, const BCP_vec< int > &del_cuts, const double petol, const double detol) const
void	pack (BCP_buffer &buf) const
Constructors and destructor
	BCP_warmstart_basis (BCP_buffer &buf)
	BCP_warmstart_basis (const char *vfirst, const char *vlast, const char *cfirst, const char *clast)
	BCP_warmstart_basis (const BCP_warmstart_basis &ws)
Private Member Functions
BCP_warmstart_basis &	operator= (const BCP_warmstart_basis &)
	BCP_warmstart_basis ()
Private Attributes
BCP_vec_change< char >	_var_stat
BCP_vec_change< char >	_cut_stat

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Detailed Description

This class describes a warmstart information that consists of basis information for structural and artificial variables.

"basic / on_upper / on_lower" info is stored on 2 bits for every variable. Only the added methods are documented in details on this page, for the inherited methods see the description of the base class.

Definition at line 24 of file BCP_warmstart_basis.hpp.

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Constructor & Destructor Documentation

BCP_warmstart_basis::BCP_warmstart_basis (   )  [inline, private]

The default constructor creates an empty WrtParent warmstart info (i.e., no change wrt the parent). This is a private method since only the empty_wrt_this() method should be able to use this form of creation. Definition at line 32 of file BCP_warmstart_basis.hpp. References _cut_stat, and _var_stat. Referenced by as_change(), clone(), and empty_wrt_this(). : _var_stat(BCP_Storage_WrtParent), _cut_stat(BCP_Storage_WrtParent) {}

BCP_warmstart_basis::BCP_warmstart_basis (  BCP_buffer &  buf  )  [inline]

Create the object by unpacking it from a buffer Definition at line 45 of file BCP_warmstart_basis.hpp. References _cut_stat, and _var_stat. : _var_stat(buf), _cut_stat(buf) {}

BCP_warmstart_basis::BCP_warmstart_basis (  const char *  vfirst, const char *  vlast, const char *  cfirst, const char *  clast )  [inline]

Create an explicitly stored warmstart info by considering the two character arrays ([vfirst,vlast) and [cfirst,clast)) as the status arrays for the variables/cuts Definition at line 50 of file BCP_warmstart_basis.hpp. References _cut_stat, and _var_stat. : _var_stat(vfirst, vlast), _cut_stat(cfirst, clast) {}

BCP_warmstart_basis::BCP_warmstart_basis (  const BCP_warmstart_basis &  ws  )  [inline]

Copy constructor Definition at line 54 of file BCP_warmstart_basis.hpp. References _cut_stat, and _var_stat. : _var_stat(ws._var_stat), _cut_stat(ws._cut_stat) {}

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Member Function Documentation

BCP_warmstart * BCP_warmstart_basis::as_change (  const BCP_warmstart *const  old_ws, const BCP_vec< int > &  del_vars, const BCP_vec< int > &  del_cuts, const double  petol, const double  detol )  const [virtual]

Return a pointer to a warmstart info describing the currently stored data as a change with respect to that stored in old_ws. However, if the currently stored data is shorter to store than the change, then this method can return a copy of the current data! The current data must be explicitly stored and old_ws must be either explicit or can contain no data. Otherwise an exception must be thrown. Parameters: old_ws  the old warmstart info del_vars  the indices of the variables that are deleted from the formulation old_ws was created for del_cuts  same for the cuts petol  primal zero tolerance detol  dual zero tolerance Implements BCP_warmstart. Definition at line 55 of file BCP_warmstart_basis.cpp. References _cut_stat, _var_stat, BCP_warmstart_basis(), storage(), and BCP_vec_change< char >::storage_size(). { const BCP_warmstart_basis* const ows = dynamic_cast<const BCP_warmstart_basis* const>(old_ws); if (!ows) throw BCP_fatal_error("BCP_warmstart_basis::as_change\n \ trying to describe a BCP_warmstart_basis as a change to a different ws!\n"); if (storage() != BCP_Storage_Explicit) throw BCP_fatal_error("BCP_warmstart_basis::as_change\n \ current data is not explicit!\n"); if (ows->storage() == BCP_Storage_WrtParent) throw BCP_fatal_error("\ BCP_warmstart_dual::as_change : old_ws is WrtParent!\n"); if (ows->storage() == BCP_Storage_NoData) return new BCP_warmstart_basis(*this); // Both are explicit BCP_warmstart_basis* ws = new BCP_warmstart_basis(); new (&ws->_var_stat) BCP_vec_change<char>(ows->_var_stat, _var_stat, del_vars); if (ws->_var_stat.storage_size() > ows->_var_stat.storage_size()) ws->_var_stat = ows->_var_stat; new (&ws->_cut_stat) BCP_vec_change<char>(ows->_cut_stat, _cut_stat, del_cuts); if (ws->_cut_stat.storage_size() > ows->_cut_stat.storage_size()) ws->_cut_stat = ows->_cut_stat; return ws; }

virtual BCP_warmstart* BCP_warmstart_basis::clone (   )  const [inline, virtual]

Make a replica of the current warmstart information. Implements BCP_warmstart. Definition at line 69 of file BCP_warmstart_basis.hpp. References BCP_warmstart_basis(). { return new BCP_warmstart_basis(*this); }

CoinWarmStart * BCP_warmstart_basis::convert_to_CoinWarmStart (   )  const [virtual]

Return an CoinwarmStart object that can be fed to the LP engine. The implementation for this class will return an CoinwarmStartBasis object. Implements BCP_warmstart. Definition at line 9 of file BCP_warmstart_basis.cpp. References _cut_stat, _var_stat, BCP_vec< T >::begin(), BCP_vec_change< char >::explicit_vector(), BCP_vec< T >::size(), and storage(). { if (storage() != BCP_Storage_Explicit) return NULL; const BCP_vec<char>& vst = _var_stat.explicit_vector(); const BCP_vec<char>& cst = _cut_stat.explicit_vector(); return new CoinWarmStartBasis(vst.size(), cst.size(), vst.begin(), cst.begin()); }

virtual BCP_warmstart* BCP_warmstart_basis::empty_wrt_this (   )  const [inline, virtual]

Create a warmstart info describing that no change should be done. This is really the task of a constructor, but BCP does not know the type of warmstart the user will use, so it will invoke this method for a warmstart that was created by the user. Tricky, isn't it? Implements BCP_warmstart. Definition at line 73 of file BCP_warmstart_basis.hpp. References BCP_warmstart_basis(). { // The default constructor creates an empty WrtParent warmstart info // (i.e., no change wrt the parent) return new BCP_warmstart_basis(); }

BCP_warmstart_basis& BCP_warmstart_basis::operator= (  const BCP_warmstart_basis &   )  [private]

The assignment operator is declared but not defined to disable it.

void BCP_warmstart_basis::pack (  BCP_buffer &  buf  )  const [inline]

Pack the warmstart info into a buffer. Definition at line 94 of file BCP_warmstart_basis.hpp. References _cut_stat, _var_stat, and BCP_vec_change< char >::pack(). { _var_stat.pack(buf); _cut_stat.pack(buf); }

BCP_storage_t BCP_warmstart_basis::storage (   )  const [virtual]

Return how the warmstarting info is stored. Implements BCP_warmstart. Definition at line 23 of file BCP_warmstart_basis.cpp. References _cut_stat, _var_stat, and BCP_vec_change< char >::storage(). Referenced by as_change(), and convert_to_CoinWarmStart(). { // The storage is WrtParent if at least one status set is WrtParent const BCP_storage_t vst = _var_stat.storage(); const BCP_storage_t cst = _cut_stat.storage(); if (vst == BCP_Storage_WrtParent || cst == BCP_Storage_WrtParent) return BCP_Storage_WrtParent; // Otherwise Explicit if at least one status set is Explicit if (vst == BCP_Storage_Explicit || cst == BCP_Storage_Explicit) return BCP_Storage_Explicit; // Otherwise it must be NoData return BCP_Storage_NoData; }

virtual int BCP_warmstart_basis::storage_size (   )  const [inline, virtual]

Return how much memory it'll take to pack this warmstart info. It is used when comparing which sort of storage is smaller. Implements BCP_warmstart. Definition at line 79 of file BCP_warmstart_basis.hpp. References _cut_stat, _var_stat, and BCP_vec_change< char >::storage_size(). { return _var_stat.storage_size() + _cut_stat.storage_size(); }

void BCP_warmstart_basis::update (  const BCP_warmstart *const  change  )  [virtual]

Update the current data with the one in the argument. If the argument is of explicit storage then just replace the current data. If it is relative and the current data is explicit then perform the update. Otherwise throw an exception. Implements BCP_warmstart. Definition at line 39 of file BCP_warmstart_basis.cpp. References _cut_stat, _var_stat, and BCP_vec_change< char >::update(). { const BCP_warmstart_basis* ch = dynamic_cast<const BCP_warmstart_basis*>(change); if (! ch) throw BCP_fatal_error("BCP_warmstart_basis::update\n \ Can't update a BCP_warmstart_basis with a different warmstart.\n"); _var_stat.update(ch->_var_stat); _cut_stat.update(ch->_cut_stat); }

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Member Data Documentation

BCP_vec_change<char> BCP_warmstart_basis::_cut_stat [private]

The stati of the cuts stored as a vector change. Definition at line 39 of file BCP_warmstart_basis.hpp. Referenced by as_change(), BCP_warmstart_basis(), convert_to_CoinWarmStart(), pack(), storage(), storage_size(), and update().

BCP_vec_change<char> BCP_warmstart_basis::_var_stat [private]

The stati of the variables stored as a vector change. Definition at line 37 of file BCP_warmstart_basis.hpp. Referenced by as_change(), BCP_warmstart_basis(), convert_to_CoinWarmStart(), pack(), storage(), storage_size(), and update().

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

• BCP_warmstart_basis.hpp
• BCP_warmstart_basis.cpp

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