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// Copyright (C) 1995 The New York Group Theory Cooperative
// See magnus/doc/COPYRIGHT for the full notice.
//
// Contents: Declarations of classes RandomAutomorphism
//
// Principal Author: Sergei Lioutikov
//
// Status: in progress
//
// Revision History:
//
// Notes:
//
// * generates random automorphisms for a free group.
// * copy constructor does logical copy.
// * this is an adoptation of the algorithm written by Roger Needham.
//
#ifndef _RANDOMAUTOMORPHISM_H_
#define _RANDOMAUTOMORPHISM_H_
#include "RandomNumbers.h"
#include "FreeGroup.h"
#include "Map.h"
//---------------------------------------------------------------------------//
//------------------------- RandomAutomorphism ------------------------------//
//---------------------------------------------------------------------------//
class RandomAutomorphism
{
public:
/////////////////////////////////////////////////////////////////////////
// //
// Constructors: //
// //
/////////////////////////////////////////////////////////////////////////
RandomAutomorphism( const FreeGroup& F, int seed );
// Giving the same `seed' you obtain the same sequence of automorphisms.
~RandomAutomorphism( );
/////////////////////////////////////////////////////////////////////////
// //
// Accessors: //
// //
/////////////////////////////////////////////////////////////////////////
VectorOf<Word> getGeneratingVector( int avgNumGens );
// `avgNumGens' gives the average number of Whitehead automorphisms to apply.
Map getAutomorphism( int avgnumGens );
// similar to `getGeneratingVector'.
private:
/////////////////////////////////////////////////////////////////////////
// //
// Data Members: //
// //
/////////////////////////////////////////////////////////////////////////
FreeGroup theGroup;
int numberOfGroupGens;
NormalRandom numGensPicker;
UniformRandom typeGenPicker;
};
#endif
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