CLHEP::MTwistEngine Class Reference

#include <MTwistEngine.h>

Inheritance diagram for CLHEP::MTwistEngine:

Public Member Functions
	MTwistEngine ()
	MTwistEngine (long seed)
	MTwistEngine (int rowIndex, int colIndex)
	MTwistEngine (std::istream &is)
virtual	~MTwistEngine ()
double	flat ()
void	flatArray (const int size, double *vect)
void	setSeed (long seed, int)
void	setSeeds (const long *seeds, int)
void	saveStatus (const char filename[]="MTwist.conf") const
void	restoreStatus (const char filename[]="MTwist.conf")
void	showStatus () const
	operator double ()
	operator float ()
	operator unsigned int ()
virtual std::ostream &	put (std::ostream &os) const
virtual std::istream &	get (std::istream &is)
virtual std::istream &	getState (std::istream &is)
std::string	name () const
std::vector< unsigned long >	put () const
bool	get (const std::vector< unsigned long > &v)
bool	getState (const std::vector< unsigned long > &v)
Public Member Functions inherited from CLHEP::HepRandomEngine
	HepRandomEngine ()
virtual	~HepRandomEngine ()
bool	operator== (const HepRandomEngine &engine)
bool	operator!= (const HepRandomEngine &engine)
long	getSeed () const
const long *	getSeeds () const

Static Public Member Functions
static std::string	beginTag ()
static std::string	engineName ()
Static Public Member Functions inherited from CLHEP::HepRandomEngine
static std::string	beginTag ()
static HepRandomEngine *	newEngine (std::istream &is)
static HepRandomEngine *	newEngine (const std::vector< unsigned long > &v)

Static Public Attributes
static const unsigned int	VECTOR_STATE_SIZE = 626

Additional Inherited Members
Static Protected Member Functions inherited from CLHEP::HepRandomEngine
static double	exponent_bit_32 ()
static double	mantissa_bit_12 ()
static double	mantissa_bit_24 ()
static double	mantissa_bit_32 ()
static double	twoToMinus_32 ()
static double	twoToMinus_48 ()
static double	twoToMinus_49 ()
static double	twoToMinus_53 ()
static double	nearlyTwoToMinus_54 ()
static bool	checkFile (std::istream &file, const std::string &filename, const std::string &classname, const std::string &methodname)
Protected Attributes inherited from CLHEP::HepRandomEngine
long	theSeed
const long *	theSeeds

Detailed Description

Author

Definition at line 34 of file MTwistEngine.h.

Constructor & Destructor Documentation

MTwistEngine() [1/4]

CLHEP::MTwistEngine::MTwistEngine

(

)

Definition at line 66 of file MTwistEngine.cc.

: HepRandomEngine()
{
  int numEngines = numberOfEngines++;
  int cycle = std::abs(int(numEngines/maxIndex));
  int curIndex = std::abs(int(numEngines%maxIndex));
  long mask = ((cycle & 0x007fffff) << 8);
  long seedlist[2];
  HepRandom::getTheTableSeeds( seedlist, curIndex );
  seedlist[0] = (seedlist[0])^mask;
  seedlist[1] = 0;
  setSeeds( seedlist, numEngines );
  count624=0;
 
  for( int i=0; i < 2000; ++i ) flat();      // Warm up just a bit
}

MTwistEngine() [2/4]

CLHEP::MTwistEngine::MTwistEngine

(

long

seed

)

Definition at line 83 of file MTwistEngine.cc.

: HepRandomEngine()
{
  long seedlist[2]={seed,17587};
  setSeeds( seedlist, 0 );
  count624=0;
  for( int i=0; i < 2000; ++i ) flat();      // Warm up just a bit
}

MTwistEngine() [3/4]

CLHEP::MTwistEngine::MTwistEngine	(	int	rowIndex,
		int	colIndex )

Definition at line 92 of file MTwistEngine.cc.

: HepRandomEngine()
{
  int cycle = std::abs(int(rowIndex/maxIndex));
  int row = std::abs(int(rowIndex%maxIndex));
  int col = std::abs(int(colIndex%2));
  long mask = (( cycle & 0x000007ff ) << 20 );
  long seedlist[2];
  HepRandom::getTheTableSeeds( seedlist, row );
  seedlist[0] = (seedlist[col])^mask;
  seedlist[1] = 690691;
  setSeeds(seedlist, 4444772);
  count624=0;
  for( int i=0; i < 2000; ++i ) flat();      // Warm up just a bit
}

MTwistEngine() [4/4]

CLHEP::MTwistEngine::MTwistEngine

(

std::istream &

is

)

Definition at line 108 of file MTwistEngine.cc.

: HepRandomEngine()
{
  is >> *this;
}

~MTwistEngine()

CLHEP::MTwistEngine::~MTwistEngine ( )

virtual

Definition at line 114 of file MTwistEngine.cc.

{}

Member Function Documentation

beginTag()

std::string CLHEP::MTwistEngine::beginTag ( )

static

Definition at line 346 of file MTwistEngine.cc.

                                    { 
  return "MTwistEngine-begin"; 
}

engineName()

static std::string CLHEP::MTwistEngine::engineName ( )

inlinestatic

Definition at line 77 of file MTwistEngine.h.

{return "MTwistEngine";}

Referenced by restoreStatus().

flat()

double CLHEP::MTwistEngine::flat ( )

virtual

Implements CLHEP::HepRandomEngine.

Definition at line 116 of file MTwistEngine.cc.

                          {
  unsigned int y;
 
   if( count624 >= N ) {
    int i;
 
    for( i=0; i < NminusM; ++i ) {
      y = (mt[i] & 0x80000000) | (mt[i+1] & 0x7fffffff);
      mt[i] = mt[i+M]       ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
    }
 
    for(    ; i < N-1    ; ++i ) {
      y = (mt[i] & 0x80000000) | (mt[i+1] & 0x7fffffff);
      mt[i] = mt[i-NminusM] ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
    }
 
    y = (mt[i] & 0x80000000) | (mt[0] & 0x7fffffff);
    mt[i] = mt[M-1] ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
 
    count624 = 0;
  }
 
  y = mt[count624];
  y ^= ( y >> 11);
  y ^= ((y << 7 ) & 0x9d2c5680);
  y ^= ((y << 15) & 0xefc60000);
  y ^= ( y >> 18);
 
  return                      y * twoToMinus_32()  +    // Scale to range 
         (mt[count624++] >> 11) * twoToMinus_53()  +    // fill remaining bits
                        nearlyTwoToMinus_54();      // make sure non-zero
}

Referenced by flatArray(), MTwistEngine(), MTwistEngine(), MTwistEngine(), and operator double().

flatArray()

void CLHEP::MTwistEngine::flatArray ( const int size, double * vect )

virtual

Implements CLHEP::HepRandomEngine.

Definition at line 149 of file MTwistEngine.cc.

                                                           {
  for( int i=0; i < size; ++i) vect[i] = flat();
}

get() [1/2]

bool CLHEP::MTwistEngine::get ( const std::vector< unsigned long > & v )

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 368 of file MTwistEngine.cc.

                                                          {
  if ((v[0] & 0xffffffffUL) != engineIDulong<MTwistEngine>()) {
    std::cerr << 
        "\nMTwistEngine get:state vector has wrong ID word - state unchanged\n";
    return false;
  }
  return getState(v);
}

get() [2/2]

std::istream & CLHEP::MTwistEngine::get ( std::istream & is )

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 328 of file MTwistEngine.cc.

{
  char beginMarker [MarkerLen];
  is >> std::ws;
  is.width(MarkerLen);  // causes the next read to the char* to be <=
            // that many bytes, INCLUDING A TERMINATION \0 
            // (Stroustrup, section 21.3.2)
  is >> beginMarker;
  if (strcmp(beginMarker,"MTwistEngine-begin")) {
     is.clear(std::ios::badbit | is.rdstate());
     std::cerr << "\nInput stream mispositioned or"
           << "\nMTwistEngine state description missing or"
           << "\nwrong engine type found." << std::endl;
     return is;
   }
  return getState(is);
}

getState() [1/2]

bool CLHEP::MTwistEngine::getState ( const std::vector< unsigned long > & v )

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 377 of file MTwistEngine.cc.

                                                               {
  if (v.size() != VECTOR_STATE_SIZE ) {
    std::cerr << 
        "\nMTwistEngine get:state vector has wrong length - state unchanged\n";
    return false;
  }
  for (int i=0; i<624; ++i) {
     mt[i]=(unsigned int)v[i+1];
  }
  count624 = (int)v[625];
  return true;
}

getState() [2/2]

std::istream & CLHEP::MTwistEngine::getState ( std::istream & is )

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 350 of file MTwistEngine.cc.

{
  char endMarker   [MarkerLen];
  is >> theSeed;
  for (int i=0; i<624; ++i)  is >> mt[i];
  is >> count624;
  is >> std::ws;
  is.width(MarkerLen);  
  is >> endMarker;
  if (strcmp(endMarker,"MTwistEngine-end")) {
     is.clear(std::ios::badbit | is.rdstate());
     std::cerr << "\nMTwistEngine state description incomplete."
           << "\nInput stream is probably mispositioned now." << std::endl;
     return is;
   }
   return is;
}

Referenced by get(), and get().

name()

std::string CLHEP::MTwistEngine::name ( ) const

virtual

Implements CLHEP::HepRandomEngine.

Definition at line 64 of file MTwistEngine.cc.

{return "MTwistEngine";}

operator double()

CLHEP::MTwistEngine::operator double ( )

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 235 of file MTwistEngine.cc.

                              {
  return flat();
}

operator float()

CLHEP::MTwistEngine::operator float ( )

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 239 of file MTwistEngine.cc.

                             {
  unsigned int y;
 
  if( count624 >= N ) {
    int i;
 
    for( i=0; i < NminusM; ++i ) {
      y = (mt[i] & 0x80000000) | (mt[i+1] & 0x7fffffff);
      mt[i] = mt[i+M]       ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
    }
 
    for(    ; i < N-1    ; ++i ) {
      y = (mt[i] & 0x80000000) | (mt[i+1] & 0x7fffffff);
      mt[i] = mt[i-NminusM] ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
    }
 
    y = (mt[i] & 0x80000000) | (mt[0] & 0x7fffffff);
    mt[i] = mt[M-1] ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
 
    count624 = 0;
  }
 
  y = mt[count624++];
  y ^= ( y >> 11);
  y ^= ((y << 7 ) & 0x9d2c5680);
  y ^= ((y << 15) & 0xefc60000);
  y ^= ( y >> 18);
 
  return (float)(y * twoToMinus_32());
}

operator unsigned int()

CLHEP::MTwistEngine::operator unsigned int ( )

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 270 of file MTwistEngine.cc.

                                    {
  unsigned int y;
 
  if( count624 >= N ) {
    int i;
 
    for( i=0; i < NminusM; ++i ) {
      y = (mt[i] & 0x80000000) | (mt[i+1] & 0x7fffffff);
      mt[i] = mt[i+M]       ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
    }
 
    for(    ; i < N-1    ; ++i ) {
      y = (mt[i] & 0x80000000) | (mt[i+1] & 0x7fffffff);
      mt[i] = mt[i-NminusM] ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
    }
 
    y = (mt[i] & 0x80000000) | (mt[0] & 0x7fffffff);
    mt[i] = mt[M-1] ^ (y >> 1) ^ ((y & 0x1) ? 0x9908b0df : 0x0 );
 
    count624 = 0;
  }
 
  y = mt[count624++];
  y ^= ( y >> 11);
  y ^= ((y << 7 ) & 0x9d2c5680);
  y ^= ((y << 15) & 0xefc60000);
  y ^= ( y >> 18);
 
  return y;
}

put() [1/2]

std::vector< unsigned long > CLHEP::MTwistEngine::put ( ) const

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 318 of file MTwistEngine.cc.

                                                  {
  std::vector<unsigned long> v;
  v.push_back (engineIDulong<MTwistEngine>());
  for (int i=0; i<624; ++i) {
     v.push_back(static_cast<unsigned long>(mt[i]));
  }
  v.push_back(count624); 
  return v;
}

put() [2/2]

std::ostream & CLHEP::MTwistEngine::put ( std::ostream & os ) const

virtual

Reimplemented from CLHEP::HepRandomEngine.

Definition at line 301 of file MTwistEngine.cc.

{
   char beginMarker[] = "MTwistEngine-begin";
   char endMarker[]   = "MTwistEngine-end";
 
   long pr = os.precision(20);
   os << " " << beginMarker << " ";
   os << theSeed << " ";
   for (int i=0; i<624; ++i) {
     os << mt[i] << "\n";
   }
   os << count624 << " ";
   os << endMarker << "\n";
   os.precision(pr);
   return os;
}

restoreStatus()

void CLHEP::MTwistEngine::restoreStatus ( const char filename[] = "MTwist.conf" )

virtual

Implements CLHEP::HepRandomEngine.

Definition at line 201 of file MTwistEngine.cc.

{
   std::ifstream inFile( filename, std::ios::in);
   if (!checkFile ( inFile, filename, engineName(), "restoreStatus" )) {
     std::cerr << "  -- Engine state remains unchanged\n";
     return;
   }
 
   if (!inFile.bad() && !inFile.eof()) {
     inFile >> theSeed;
     for (int i=0; i<624; ++i) inFile >> mt[i];
     inFile >> count624;
   }
}

saveStatus()

void CLHEP::MTwistEngine::saveStatus ( const char filename[] = "MTwist.conf" ) const

virtual

Implements CLHEP::HepRandomEngine.

Definition at line 190 of file MTwistEngine.cc.

{
   std::ofstream outFile( filename, std::ios::out ) ;
   if (!outFile.bad()) {
     outFile << theSeed << std::endl;
     for (int i=0; i<624; ++i) outFile <<std::setprecision(20) << mt[i] << " ";
     outFile << std::endl;
     outFile << count624 << std::endl;
   }
}

setSeed()

void CLHEP::MTwistEngine::setSeed ( long seed, int k )

virtual

Implements CLHEP::HepRandomEngine.

Definition at line 153 of file MTwistEngine.cc.

                                           {
 
  // MF 11/15/06 - Change seeding algorithm to a newer one recommended 
  //               by Matsumoto: The original algorithm was 
  //           mt[i] = (69069 * mt[i-1]) & 0xffffffff and this gives
  //           problems when the seed bit pattern has lots of zeros
  //           (for example, 0x08000000).  Savanah bug #17479.
 
  theSeed = seed ? seed : 4357;
  int mti;
  const int N1=624;
  mt[0] = (unsigned int) (theSeed&0xffffffffUL);
  for (mti=1; mti<N1; mti++) {
    mt[mti] = (1812433253UL * (mt[mti-1] ^ (mt[mti-1] >> 30)) + mti); 
        /* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
        /* In the previous versions, MSBs of the seed affect   */
        /* only MSBs of the array mt[].                        */
        /* 2002/01/09 modified by Makoto Matsumoto             */
    mt[mti] &= 0xffffffffUL;
        /* for >32 bit machines */
  }
  for( int i=1; i < 624; ++i ) {
    mt[i] ^= k;         // MF 9/16/98: distinguish starting points
  }
  // MF 11/15/06 This distinction of starting points based on values of k
  //             is kept even though the seeding algorithm itself is improved.
}

Referenced by setSeeds().

setSeeds()

void CLHEP::MTwistEngine::setSeeds ( const long * seeds, int k )

virtual

Implements CLHEP::HepRandomEngine.

Definition at line 181 of file MTwistEngine.cc.

                                                    {
  setSeed( (*seeds ? *seeds : 43571346), k );
  int i;
  for( i=1; i < 624; ++i ) {
    mt[i] = ( seeds[1] + mt[i] ) & 0xffffffff; // MF 9/16/98 
  }
  theSeeds = seeds;
}

Referenced by MTwistEngine(), MTwistEngine(), and MTwistEngine().

showStatus()

void CLHEP::MTwistEngine::showStatus ( ) const

virtual

Implements CLHEP::HepRandomEngine.

Definition at line 216 of file MTwistEngine.cc.

{
   std::cout << std::endl;
   std::cout << "--------- MTwist engine status ---------" << std::endl;
   std::cout << std::setprecision(20);
   std::cout << " Initial seed      = " << theSeed << std::endl;
   std::cout << " Current index     = " << count624 << std::endl;
   std::cout << " Array status mt[] = " << std::endl;
   // 2014/06/06  L Garren
   // the final line has 4 elements, not 5
   for (int i=0; i<620; i+=5) {
     std::cout << mt[i]   << " " << mt[i+1] << " " << mt[i+2] << " " 
           << mt[i+3] << " " << mt[i+4] << "\n";
   }
   std::cout << mt[620]   << " " << mt[621] << " " << mt[622] << " " 
         << mt[623]  << std::endl;
   std::cout << "----------------------------------------" << std::endl;
}

Member Data Documentation

VECTOR_STATE_SIZE

const unsigned int CLHEP::MTwistEngine::VECTOR_STATE_SIZE = 626

static

Definition at line 83 of file MTwistEngine.h.

Referenced by getState().

---

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

• MTwistEngine.h
• MTwistEngine.cc