C++ (Qt)float RandNorm( int num ){ float sum = 0.0f; for (int i = 0; i < num; ++i) sum += (float) qrand() / RAND_MAX; return sum / num;}
C++ (Qt)// MersenneTwister.h// Mersenne Twister random number generator -- a C++ class MTRand// Based on code by Makoto Matsumoto, Takuji Nishimura, and Shawn Cokus// Richard J. Wagner v1.1 28 September 2009 wagnerr@umich.edu // The Mersenne Twister is an algorithm for generating random numbers. It// was designed with consideration of the flaws in various other generators.// The period, 2^19937-1, and the order of equidistribution, 623 dimensions,// are far greater. The generator is also fast; it avoids multiplication and// division, and it benefits from caches and pipelines. For more information// see the inventors' web page at// http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html // Reference// M. Matsumoto and T. Nishimura, "Mersenne Twister: A 623-Dimensionally// Equidistributed Uniform Pseudo-Random Number Generator", ACM Transactions on// Modeling and Computer Simulation, Vol. 8, No. 1, January 1998, pp 3-30. // Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,// Copyright (C) 2000 - 2009, Richard J. Wagner// All rights reserved.// // Redistribution and use in source and binary forms, with or without// modification, are permitted provided that the following conditions// are met:// // 1. Redistributions of source code must retain the above copyright// notice, this list of conditions and the following disclaimer.//// 2. Redistributions in binary form must reproduce the above copyright// notice, this list of conditions and the following disclaimer in the// documentation and/or other materials provided with the distribution.//// 3. The names of its contributors may not be used to endorse or promote // products derived from this software without specific prior written // permission.// // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE// POSSIBILITY OF SUCH DAMAGE. // The original code included the following notice:// // When you use this, send an email to: m-mat@math.sci.hiroshima-u.ac.jp// with an appropriate reference to your work.// // It would be nice to CC: wagnerr@umich.edu and Cokus@math.washington.edu// when you write. #ifndef MERSENNETWISTER_H#define MERSENNETWISTER_H // Not thread safe (unless auto-initialization is avoided and each thread has// its own MTRand object) #include <iostream>#include <climits>#include <cstdio>#include <ctime>#include <cmath> class MTRand {// Datapublic: typedef unsigned long uint32; // unsigned integer type, at least 32 bits enum { N = 624 }; // length of state vector enum { SAVE = N + 1 }; // length of array for save() protected: enum { M = 397 }; // period parameter uint32 state[N]; // internal state uint32 *pNext; // next value to get from state int left; // number of values left before reload needed // Methodspublic: MTRand( const uint32 oneSeed ); // initialize with a simple uint32 MTRand( uint32 *const bigSeed, uint32 const seedLength = N ); // or array MTRand(); // auto-initialize with /dev/urandom or time() and clock() MTRand( const MTRand& o ); // copy // Do NOT use for CRYPTOGRAPHY without securely hashing several returned // values together, otherwise the generator state can be learned after // reading 624 consecutive values. // Access to 32-bit random numbers uint32 randInt(); // integer in [0,2^32-1] uint32 randInt( const uint32 n ); // integer in [0,n] for n < 2^32 double rand(); // real number in [0,1] double rand( const double n ); // real number in [0,n] double randExc(); // real number in [0,1) double randExc( const double n ); // real number in [0,n) double randDblExc(); // real number in (0,1) double randDblExc( const double n ); // real number in (0,n) double operator()(); // same as rand() // Access to 53-bit random numbers (capacity of IEEE double precision) double rand53(); // real number in [0,1) // Access to nonuniform random number distributions double randNorm( const double mean = 0.0, const double stddev = 1.0 ); // Re-seeding functions with same behavior as initializers void seed( const uint32 oneSeed ); void seed( uint32 *const bigSeed, const uint32 seedLength = N ); void seed(); // Saving and loading generator state void save( uint32* saveArray ) const; // to array of size SAVE void load( uint32 *const loadArray ); // from such array friend std::ostream& operator<<( std::ostream& os, const MTRand& mtrand ); friend std::istream& operator>>( std::istream& is, MTRand& mtrand ); MTRand& operator=( const MTRand& o ); protected: void initialize( const uint32 oneSeed ); void reload(); uint32 hiBit( const uint32 u ) const { return u & 0x80000000UL; } uint32 loBit( const uint32 u ) const { return u & 0x00000001UL; } uint32 loBits( const uint32 u ) const { return u & 0x7fffffffUL; } uint32 mixBits( const uint32 u, const uint32 v ) const { return hiBit(u) | loBits(v); } uint32 magic( const uint32 u ) const { return loBit(u) ? 0x9908b0dfUL : 0x0UL; } uint32 twist( const uint32 m, const uint32 s0, const uint32 s1 ) const { return m ^ (mixBits(s0,s1)>>1) ^ magic(s1); } static uint32 hash( time_t t, clock_t c ); protected: double sqrs; double r1; double r2; double rho; bool valid;}; // Functions are defined in order of usage to assist inlining inline MTRand::uint32 MTRand::hash( time_t t, clock_t c ){ // Get a uint32 from t and c // Better than uint32(x) in case x is floating point in [0,1] // Based on code by Lawrence Kirby (fred@genesis.demon.co.uk) static uint32 differ = 0; // guarantee time-based seeds will change uint32 h1 = 0; unsigned char *p = (unsigned char *) &t; for( size_t i = 0; i < sizeof(t); ++i ) { h1 *= UCHAR_MAX + 2U; h1 += p[i]; } uint32 h2 = 0; p = (unsigned char *) &c; for( size_t j = 0; j < sizeof(c); ++j ) { h2 *= UCHAR_MAX + 2U; h2 += p[j]; } return ( h1 + differ++ ) ^ h2;} inline void MTRand::initialize( const uint32 seed ){ // Initialize generator state with seed // See Knuth TAOCP Vol 2, 3rd Ed, p.106 for multiplier. // In previous versions, most significant bits (MSBs) of the seed affect // only MSBs of the state array. Modified 9 Jan 2002 by Makoto Matsumoto. register uint32 *s = state; register uint32 *r = state; register int i = 1; *s++ = seed & 0xffffffffUL; for( ; i < N; ++i ) { *s++ = ( 1812433253UL * ( *r ^ (*r >> 30) ) + i ) & 0xffffffffUL; r++; }} inline void MTRand::reload(){ // Generate N new values in state // Made clearer and faster by Matthew Bellew (matthew.bellew@home.com) static const int MmN = int(M) - int(N); // in case enums are unsigned register uint32 *p = state; register int i; for( i = N - M; i--; ++p ) *p = twist( p[M], p[0], p[1] ); for( i = M; --i; ++p ) *p = twist( p[MmN], p[0], p[1] ); *p = twist( p[MmN], p[0], state[0] ); left = N, pNext = state;} inline void MTRand::seed( const uint32 oneSeed ){ // Seed the generator with a simple uint32 initialize(oneSeed); reload();} inline void MTRand::seed( uint32 *const bigSeed, const uint32 seedLength ){ // Seed the generator with an array of uint32's // There are 2^19937-1 possible initial states. This function allows // all of those to be accessed by providing at least 19937 bits (with a // default seed length of N = 624 uint32's). Any bits above the lower 32 // in each element are discarded. // Just call seed() if you want to get array from /dev/urandom initialize(19650218UL); register int i = 1; register uint32 j = 0; register int k = ( N > seedLength ? (int)N : seedLength ); for( ; k; --k ) { state[i] = state[i] ^ ( (state[i-1] ^ (state[i-1] >> 30)) * 1664525UL ); state[i] += ( bigSeed[j] & 0xffffffffUL ) + j; state[i] &= 0xffffffffUL; ++i; ++j; if( i >= N ) { state[0] = state[N-1]; i = 1; } if( j >= seedLength ) j = 0; } for( k = N - 1; k; --k ) { state[i] = state[i] ^ ( (state[i-1] ^ (state[i-1] >> 30)) * 1566083941UL ); state[i] -= i; state[i] &= 0xffffffffUL; ++i; if( i >= N ) { state[0] = state[N-1]; i = 1; } } state[0] = 0x80000000UL; // MSB is 1, assuring non-zero initial array reload();} inline void MTRand::seed(){ // Seed the generator with an array from /dev/urandom if available // Otherwise use a hash of time() and clock() values // First try getting an array from /dev/urandom FILE* urandom = fopen( "/dev/urandom", "rb" ); if( urandom ) { uint32 bigSeed[N]; register uint32 *s = bigSeed; register int i = N; register bool success = true; while( success && i-- ) success = fread( s++, sizeof(uint32), 1, urandom ); fclose(urandom); if( success ) { seed( bigSeed, N ); return; } } // Was not successful, so use time() and clock() instead seed( hash( time(NULL), clock() ) );} inline MTRand::MTRand( const uint32 oneSeed ){ seed(oneSeed); valid = false;} inline MTRand::MTRand( uint32 *const bigSeed, const uint32 seedLength ){ seed(bigSeed,seedLength); valid = false;} inline MTRand::MTRand(){ seed(); valid = false;} inline MTRand::MTRand( const MTRand& o ){ register const uint32 *t = o.state; register uint32 *s = state; register int i = N; for( ; i--; *s++ = *t++ ) {} left = o.left; pNext = &state[N-left]; valid = o.valid; if (valid) { r1 = o.r1; r2 = o.r2; rho = o.rho; sqrs = o.sqrs; }} inline MTRand::uint32 MTRand::randInt(){ // Pull a 32-bit integer from the generator state // Every other access function simply transforms the numbers extracted here if( left == 0 ) reload(); --left; register uint32 s1; s1 = *pNext++; s1 ^= (s1 >> 11); s1 ^= (s1 << 7) & 0x9d2c5680UL; s1 ^= (s1 << 15) & 0xefc60000UL; return ( s1 ^ (s1 >> 18) );} inline MTRand::uint32 MTRand::randInt( const uint32 n ){ // Find which bits are used in n // Optimized by Magnus Jonsson (magnus@smartelectronix.com) uint32 used = n; used |= used >> 1; used |= used >> 2; used |= used >> 4; used |= used >> 8; used |= used >> 16; // Draw numbers until one is found in [0,n] uint32 i; do i = randInt() & used; // toss unused bits to shorten search while( i > n ); return i;} inline double MTRand::rand() { return double(randInt()) * (1.0/4294967295.0); } inline double MTRand::rand( const double n ) { return rand() * n; } inline double MTRand::randExc() { return double(randInt()) * (1.0/4294967296.0); } inline double MTRand::randExc( const double n ) { return randExc() * n; } inline double MTRand::randDblExc() { return ( double(randInt()) + 0.5 ) * (1.0/4294967296.0); } inline double MTRand::randDblExc( const double n ) { return randDblExc() * n; } inline double MTRand::rand53(){ uint32 a = randInt() >> 5, b = randInt() >> 6; return ( a * 67108864.0 + b ) * (1.0/9007199254740992.0); // by Isaku Wada} inline double MTRand::randNorm( const double mean, const double stddev ){ // Return a real number from a normal (Gaussian) distribution with given // mean and standard deviation by polar form of Box-Muller transformation /* double x, y, r; do { x = 2.0 * rand() - 1.0; y = 2.0 * rand() - 1.0; r = x * x + y * y; } while ( r >= 1.0 || r == 0.0 ); double s = sqrt( -2.0 * log(r) / r ); return mean + x * s * stddev; */ if (!valid) { do { r1 = 2.0 * rand() - 1.0; r2 = 2.0 * rand() - 1.0; sqrs = r1 * r1 + r2 * r2; } while (sqrs >= 1.0 || sqrs == 0.0); rho = sqrt(-2.0 * log(sqrs)/sqrs); valid = true; } else { valid = false; } return rho * (valid ? r1 : r2) * stddev + mean;} inline double MTRand::operator()(){ return rand();} inline void MTRand::save( uint32* saveArray ) const{ register const uint32 *s = state; register uint32 *sa = saveArray; register int i = N; for( ; i--; *sa++ = *s++ ) {} *sa = left;} inline void MTRand::load( uint32 *const loadArray ){ register uint32 *s = state; register uint32 *la = loadArray; register int i = N; for( ; i--; *s++ = *la++ ) {} left = *la; pNext = &state[N-left];} inline std::ostream& operator<<( std::ostream& os, const MTRand& mtrand ){ register const MTRand::uint32 *s = mtrand.state; register int i = mtrand.N; for( ; i--; os << *s++ << "\t" ) {} return os << mtrand.left;} inline std::istream& operator>>( std::istream& is, MTRand& mtrand ){ register MTRand::uint32 *s = mtrand.state; register int i = mtrand.N; for( ; i--; is >> *s++ ) {} is >> mtrand.left; mtrand.pNext = &mtrand.state[mtrand.N-mtrand.left]; return is;} inline MTRand& MTRand::operator=( const MTRand& o ){ if( this == &o ) return (*this); register const uint32 *t = o.state; register uint32 *s = state; register int i = N; for( ; i--; *s++ = *t++ ) {} left = o.left; pNext = &state[N-left]; valid = o.valid; if (valid) { sqrs = o.sqrs; r1 = o.r1; r2 = o.r2; rho = o.rho; } return (*this);} #endif // MERSENNETWISTER_H // Change log://// v0.1 - First release on 15 May 2000// - Based on code by Makoto Matsumoto, Takuji Nishimura, and Shawn Cokus// - Translated from C to C++// - Made completely ANSI compliant// - Designed convenient interface for initialization, seeding, and// obtaining numbers in default or user-defined ranges// - Added automatic seeding from /dev/urandom or time() and clock()// - Provided functions for saving and loading generator state//// v0.2 - Fixed bug which reloaded generator one step too late//// v0.3 - Switched to clearer, faster reload() code from Matthew Bellew//// v0.4 - Removed trailing newline in saved generator format to be consistent// with output format of built-in types//// v0.5 - Improved portability by replacing static const int's with enum's and// clarifying return values in seed(); suggested by Eric Heimburg// - Removed MAXINT constant; use 0xffffffffUL instead//// v0.6 - Eliminated seed overflow when uint32 is larger than 32 bits// - Changed integer [0,n] generator to give better uniformity//// v0.7 - Fixed operator precedence ambiguity in reload()// - Added access for real numbers in (0,1) and (0,n)//// v0.8 - Included time.h header to properly support time_t and clock_t//// v1.0 - Revised seeding to match 26 Jan 2002 update of Nishimura and Matsumoto// - Allowed for seeding with arrays of any length// - Added access for real numbers in [0,1) with 53-bit resolution// - Added access for real numbers from normal (Gaussian) distributions// - Increased overall speed by optimizing twist()// - Doubled speed of integer [0,n] generation// - Fixed out-of-range number generation on 64-bit machines// - Improved portability by substituting literal constants for long enum's// - Changed license from GNU LGPL to BSD//// v1.1 - Corrected parameter label in randNorm from "variance" to "stddev"// - Changed randNorm algorithm from basic to polar form for efficiency// - Updated includes from deprecated <xxxx.h> to standard <cxxxx> forms// - Cleaned declarations and definitions to please Intel compiler// - Revised twist() operator to work on ones'-complement machines// - Fixed reload() function to work when N and M are unsigned// - Added copy constructor and copy operator from Salvador Espana
C++ (Qt)#include <random> std:: normal_distribution<double> distribution(mean, sd);std::mt19937 engine; // Mersenne Twisterdouble random = distribution(engine);
gcc --version
QtSDK\mingw\bin\gcc.exe
