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root/group/trunk/OOPSE-4/src/math/MersenneTwister.hpp
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Comparing trunk/OOPSE-4/src/math/MersenneTwister.hpp (file contents):
Revision 2076 by tim, Wed Mar 2 15:36:14 2005 UTC vs.
Revision 2204 by gezelter, Fri Apr 15 22:04:00 2005 UTC

# Line 69 | Line 69 | class MTRand {
69   #include <vector>
70   namespace oopse {
71  
72 < class MTRand {
73 < // Data
74 < public:
75 <        typedef unsigned long uint32;  // unsigned integer type, at least 32 bits
72 >  class MTRand {
73 >    // Data
74 >  public:
75 >    typedef unsigned long uint32;  // unsigned integer type, at least 32 bits
76          
77 <        enum { N = 624 };       // length of state vector
78 <        enum { SAVE = N + 1 };  // length of array for save()
77 >    enum { N = 624 };       // length of state vector
78 >    enum { SAVE = N + 1 };  // length of array for save()
79  
80 < private:
81 <        enum { M = 397 };  // period parameter
80 >  private:
81 >    enum { M = 397 };  // period parameter
82          
83 <        uint32 state[N];   // internal state
84 <        uint32 *pNext;     // next value to get from state
85 <        int left;          // number of values left before reload needed
86 <        int nstrides_;
87 <        int stride_;
83 >    uint32 state[N];   // internal state
84 >    uint32 *pNext;     // next value to get from state
85 >    int left;          // number of values left before reload needed
86 >    int nstrides_;
87 >    int stride_;
88  
89 < //Methods
90 < public:
91 <        MTRand( const uint32& oneSeed, int nstrides, int stride);  // initialize with a simple uint32
92 <        MTRand( uint32 *const bigSeed, uint32 const seedLength, int nstrides, int stride);  // or an array
93 <        MTRand(int nstrides, int stride);  // auto-initialize with /dev/urandom or time() and clock()
89 >    //Methods
90 >  public:
91 >    MTRand( const uint32& oneSeed, int nstrides, int stride);  // initialize with a simple uint32
92 >    MTRand( uint32 *const bigSeed, uint32 const seedLength, int nstrides, int stride);  // or an array
93 >    MTRand(int nstrides, int stride);  // auto-initialize with /dev/urandom or time() and clock()
94          
95 <        // Do NOT use for CRYPTOGRAPHY without securely hashing several returned
96 <        // values together, otherwise the generator state can be learned after
97 <        // reading 624 consecutive values.
95 >    // Do NOT use for CRYPTOGRAPHY without securely hashing several returned
96 >    // values together, otherwise the generator state can be learned after
97 >    // reading 624 consecutive values.
98          
99 <        // Access to 32-bit random numbers
100 <        double rand();                          // real number in [0,1]
101 <        double rand( const double& n );         // real number in [0,n]
102 <        double randExc();                       // real number in [0,1)
103 <        double randExc( const double& n );      // real number in [0,n)
104 <        double randDblExc();                    // real number in (0,1)
105 <        double randDblExc( const double& n );   // real number in (0,n)
106 <        uint32 randInt();                       // integer in [0,2^32-1] (modified for striding)
107 <        uint32 rawRandInt();                    // original randInt
108 <        uint32 randInt( const uint32& n );      // integer in [0,n] for n < 2^32
109 <        double operator()() { return rand(); }  // same as rand()
99 >    // Access to 32-bit random numbers
100 >    double rand();                          // real number in [0,1]
101 >    double rand( const double& n );         // real number in [0,n]
102 >    double randExc();                       // real number in [0,1)
103 >    double randExc( const double& n );      // real number in [0,n)
104 >    double randDblExc();                    // real number in (0,1)
105 >    double randDblExc( const double& n );   // real number in (0,n)
106 >    uint32 randInt();                       // integer in [0,2^32-1] (modified for striding)
107 >    uint32 rawRandInt();                    // original randInt
108 >    uint32 randInt( const uint32& n );      // integer in [0,n] for n < 2^32
109 >    double operator()() { return rand(); }  // same as rand()
110          
111 <        // Access to 53-bit random numbers (capacity of IEEE double precision)
112 <        double rand53();  // real number in [0,1)
111 >    // Access to 53-bit random numbers (capacity of IEEE double precision)
112 >    double rand53();  // real number in [0,1)
113          
114 <        // Access to nonuniform random number distributions
115 <        double randNorm( const double& mean = 0.0, const double& variance = 0.0 );
114 >    // Access to nonuniform random number distributions
115 >    double randNorm( const double& mean = 0.0, const double& variance = 0.0 );
116          
117 <        // Re-seeding functions with same behavior as initializers
118 <        void seed( const uint32 oneSeed );
119 <        void seed( uint32 *const bigSeed, const uint32 seedLength = N );
120 <        void seed();
117 >    // Re-seeding functions with same behavior as initializers
118 >    void seed( const uint32 oneSeed );
119 >    void seed( uint32 *const bigSeed, const uint32 seedLength = N );
120 >    void seed();
121  
122 <        std::vector<uint32>generateSeeds();    
122 >    std::vector<uint32>generateSeeds();
123          
124 <        // Saving and loading generator state
125 <        void save( uint32* saveArray ) const;  // to array of size SAVE
126 <        void load( uint32 *const loadArray );  // from such array
127 <        friend std::ostream& operator<<( std::ostream& os, const MTRand& mtrand );
128 <        friend std::istream& operator>>( std::istream& is, MTRand& mtrand );
124 >    // Saving and loading generator state
125 >    void save( uint32* saveArray ) const;  // to array of size SAVE
126 >    void load( uint32 *const loadArray );  // from such array
127 >    friend std::ostream& operator<<( std::ostream& os, const MTRand& mtrand );
128 >    friend std::istream& operator>>( std::istream& is, MTRand& mtrand );
129  
130 < protected:
131 <        void initialize( const uint32 oneSeed );
132 <        void reload();
133 <        uint32 hiBit( const uint32& u ) const { return u & 0x80000000UL; }
134 <        uint32 loBit( const uint32& u ) const { return u & 0x00000001UL; }
135 <        uint32 loBits( const uint32& u ) const { return u & 0x7fffffffUL; }
136 <        uint32 mixBits( const uint32& u, const uint32& v ) const
137 <                { return hiBit(u) | loBits(v); }
138 <        uint32 twist( const uint32& m, const uint32& s0, const uint32& s1 ) const
139 <                { return m ^ (mixBits(s0,s1)>>1) ^ (-loBit(s1) & 0x9908b0dfUL); }
140 <        static uint32 hash( time_t t, clock_t c );
141 < };
130 >  protected:
131 >    void initialize( const uint32 oneSeed );
132 >    void reload();
133 >    uint32 hiBit( const uint32& u ) const { return u & 0x80000000UL; }
134 >    uint32 loBit( const uint32& u ) const { return u & 0x00000001UL; }
135 >    uint32 loBits( const uint32& u ) const { return u & 0x7fffffffUL; }
136 >    uint32 mixBits( const uint32& u, const uint32& v ) const
137 >    { return hiBit(u) | loBits(v); }
138 >    uint32 twist( const uint32& m, const uint32& s0, const uint32& s1 ) const
139 >    { return m ^ (mixBits(s0,s1)>>1) ^ (-loBit(s1) & 0x9908b0dfUL); }
140 >    static uint32 hash( time_t t, clock_t c );
141 >  };
142  
143  
144 < inline MTRand::MTRand( const uint32& oneSeed, int nstrides, int stride) : nstrides_(nstrides), stride_(stride) {
144 >  inline MTRand::MTRand( const uint32& oneSeed, int nstrides, int stride) : nstrides_(nstrides), stride_(stride) {
145      assert(stride_ < nstrides_ && stride_ >= 0);
146      seed(oneSeed);
147 < }
147 >  }
148  
149 < inline MTRand::MTRand( uint32 *const bigSeed, const uint32 seedLength, int nstrides, int stride) : nstrides_(nstrides), stride_(stride) {
149 >  inline MTRand::MTRand( uint32 *const bigSeed, const uint32 seedLength, int nstrides, int stride) : nstrides_(nstrides), stride_(stride) {
150      assert(stride_ < nstrides_ && stride_ >= 0);
151      seed(bigSeed,seedLength);
152 < }
152 >  }
153  
154 < inline MTRand::MTRand(int nstrides, int stride) : nstrides_(nstrides), stride_(stride){
154 >  inline MTRand::MTRand(int nstrides, int stride)       : nstrides_(nstrides), stride_(stride){
155      assert(stride_ < nstrides_ && stride_ >= 0);
156      seed();
157 < }
157 >  }
158  
159 < inline double MTRand::rand()
160 <        { return double(randInt()) * (1.0/4294967295.0); }
159 >  inline double MTRand::rand()
160 >  { return double(randInt()) * (1.0/4294967295.0); }
161  
162 < inline double MTRand::rand( const double& n )
163 <        { return rand() * n; }
162 >  inline double MTRand::rand( const double& n )
163 >  { return rand() * n; }
164  
165 < inline double MTRand::randExc()
166 <        { return double(randInt()) * (1.0/4294967296.0); }
165 >  inline double MTRand::randExc()
166 >  { return double(randInt()) * (1.0/4294967296.0); }
167  
168 < inline double MTRand::randExc( const double& n )
169 <        { return randExc() * n; }
168 >  inline double MTRand::randExc( const double& n )
169 >  { return randExc() * n; }
170  
171 < inline double MTRand::randDblExc()
172 <        { return ( double(randInt()) + 0.5 ) * (1.0/4294967296.0); }
171 >  inline double MTRand::randDblExc()
172 >  { return ( double(randInt()) + 0.5 ) * (1.0/4294967296.0); }
173  
174 < inline double MTRand::randDblExc( const double& n )
175 <        { return randDblExc() * n; }
174 >  inline double MTRand::randDblExc( const double& n )
175 >  { return randDblExc() * n; }
176  
177 < inline double MTRand::rand53()
178 < {
179 <        uint32 a = randInt() >> 5, b = randInt() >> 6;
180 <        return ( a * 67108864.0 + b ) * (1.0/9007199254740992.0);  // by Isaku Wada
181 < }
177 >  inline double MTRand::rand53()
178 >  {
179 >    uint32 a = randInt() >> 5, b = randInt() >> 6;
180 >    return ( a * 67108864.0 + b ) * (1.0/9007199254740992.0);  // by Isaku Wada
181 >  }
182  
183 < inline double MTRand::randNorm( const double& mean, const double& variance )
184 < {
185 <        // Return a real number from a normal (Gaussian) distribution with given
186 <        // mean and variance by Box-Muller method
187 <        double r = sqrt( -2.0 * log( 1.0-randDblExc()) ) * variance;
188 <        double phi = 2.0 * 3.14159265358979323846264338328 * randExc();
189 <        return mean + r * cos(phi);
190 < }
183 >  inline double MTRand::randNorm( const double& mean, const double& variance )
184 >  {
185 >    // Return a real number from a normal (Gaussian) distribution with given
186 >    // mean and variance by Box-Muller method
187 >    double r = sqrt( -2.0 * log( 1.0-randDblExc()) ) * variance;
188 >    double phi = 2.0 * 3.14159265358979323846264338328 * randExc();
189 >    return mean + r * cos(phi);
190 >  }
191  
192 < /**
193 < * This function is modified from the original to allow for random
194 < * streams on parallel jobs.  It now takes numbers from by striding
195 < * through the random stream and picking up only one of the random
196 < * numbers per nstrides_.  The number it picks is the stride_'th
197 < * number in the stride sequence.  
198 < */
199 < inline MTRand::uint32 MTRand::randInt() {
192 >  /**
193 >   * This function is modified from the original to allow for random
194 >   * streams on parallel jobs.  It now takes numbers from by striding
195 >   * through the random stream and picking up only one of the random
196 >   * numbers per nstrides_.  The number it picks is the stride_'th
197 >   * number in the stride sequence.  
198 >   */
199 >  inline MTRand::uint32 MTRand::randInt() {
200  
201 <  std::vector<uint32> ranNums(nstrides_);
201 >    std::vector<uint32> ranNums(nstrides_);
202    
203 <  for (int i = 0; i < nstrides_; ++i) {
204 <    ranNums[i] = rawRandInt();
205 <  }
203 >    for (int i = 0; i < nstrides_; ++i) {
204 >      ranNums[i] = rawRandInt();
205 >    }
206    
207 <  return ranNums[stride_];
208 < }
207 >    return ranNums[stride_];
208 >  }
209  
210 < /**
211 < * This is the original randInt function which implements the mersenne
212 < * twister.
213 < */
214 < inline MTRand::uint32 MTRand::rawRandInt()
215 < {
216 <        // Pull a 32-bit integer from the generator state
217 <        // Every other access function simply transforms the numbers extracted here
210 >  /**
211 >   * This is the original randInt function which implements the mersenne
212 >   * twister.
213 >   */
214 >  inline MTRand::uint32 MTRand::rawRandInt()
215 >  {
216 >    // Pull a 32-bit integer from the generator state
217 >    // Every other access function simply transforms the numbers extracted here
218          
219 <        if( left == 0 ) reload();
220 <        --left;
219 >    if( left == 0 ) reload();
220 >    --left;
221                  
222 <        register uint32 s1;
223 <        s1 = *pNext++;
224 <        s1 ^= (s1 >> 11);
225 <        s1 ^= (s1 <<  7) & 0x9d2c5680UL;
226 <        s1 ^= (s1 << 15) & 0xefc60000UL;
227 <        return ( s1 ^ (s1 >> 18) );
228 < }
222 >    register uint32 s1;
223 >    s1 = *pNext++;
224 >    s1 ^= (s1 >> 11);
225 >    s1 ^= (s1 <<  7) & 0x9d2c5680UL;
226 >    s1 ^= (s1 << 15) & 0xefc60000UL;
227 >    return ( s1 ^ (s1 >> 18) );
228 >  }
229  
230 < inline MTRand::uint32 MTRand::randInt( const uint32& n )
231 < {
232 <        // Find which bits are used in n
233 <        // Optimized by Magnus Jonsson (magnus@smartelectronix.com)
234 <        uint32 used = n;
235 <        used |= used >> 1;
236 <        used |= used >> 2;
237 <        used |= used >> 4;
238 <        used |= used >> 8;
239 <        used |= used >> 16;
240 <        
241 <        // Draw numbers until one is found in [0,n]
242 <        uint32 i;
243 <        do
244 <                i = randInt() & used;  // toss unused bits to shorten search
245 <        while( i > n );
246 <        return i;
247 < }
248 <
249 <
250 < inline void MTRand::seed( const uint32 oneSeed )
251 < {
252 <        // Seed the generator with a simple uint32
253 <        initialize(oneSeed);
254 <        reload();
255 < }
256 <
257 <
258 < inline void MTRand::seed( uint32 *const bigSeed, const uint32 seedLength )
259 < {
260 <        // Seed the generator with an array of uint32's
261 <        // There are 2^19937-1 possible initial states.  This function allows
262 <        // all of those to be accessed by providing at least 19937 bits (with a
263 <        // default seed length of N = 624 uint32's).  Any bits above the lower 32
264 <        // in each element are discarded.
265 <        // Just call seed() if you want to get array from /dev/urandom
266 <        initialize(19650218UL);
267 <        register int i = 1;
268 <        register uint32 j = 0;
269 <        register int k = ( N > seedLength ? N : seedLength );
270 <        for( ; k; --k )
271 <        {
272 <                state[i] =
273 <                        state[i] ^ ( (state[i-1] ^ (state[i-1] >> 30)) * 1664525UL );
274 <                state[i] += ( bigSeed[j] & 0xffffffffUL ) + j;
275 <                state[i] &= 0xffffffffUL;
276 <                ++i;  ++j;
277 <                if( i >= N ) { state[0] = state[N-1];  i = 1; }
278 <                if( j >= seedLength ) j = 0;
279 <        }
280 <        for( k = N - 1; k; --k )
281 <        {
282 <                state[i] =
283 <                        state[i] ^ ( (state[i-1] ^ (state[i-1] >> 30)) * 1566083941UL );
284 <                state[i] -= i;
285 <                state[i] &= 0xffffffffUL;
286 <                ++i;
287 <                if( i >= N ) { state[0] = state[N-1];  i = 1; }
288 <        }
289 <        state[0] = 0x80000000UL;  // MSB is 1, assuring non-zero initial array
290 <        reload();
291 < }
292 <
293 <
294 < inline void MTRand::seed()
295 < {
296 <  std::vector<uint32> seeds;
297 <
298 <  seeds = generateSeeds();
230 >  inline MTRand::uint32 MTRand::randInt( const uint32& n )
231 >  {
232 >    // Find which bits are used in n
233 >    // Optimized by Magnus Jonsson (magnus@smartelectronix.com)
234 >    uint32 used = n;
235 >    used |= used >> 1;
236 >    used |= used >> 2;
237 >    used |= used >> 4;
238 >    used |= used >> 8;
239 >    used |= used >> 16;
240 >        
241 >    // Draw numbers until one is found in [0,n]
242 >    uint32 i;
243 >    do
244 >      i = randInt() & used;  // toss unused bits to shorten search
245 >    while( i > n );
246 >    return i;
247 >  }
248  
249 <  if (seeds.size() == 1) {
250 <    seed( seeds[0] );
251 <  } else {
252 <    seed( &seeds[0], seeds.size() );
249 >
250 >  inline void MTRand::seed( const uint32 oneSeed )
251 >  {
252 >    // Seed the generator with a simple uint32
253 >    initialize(oneSeed);
254 >    reload();
255    }
305 – }
256  
257  
258 < inline std::vector<MTRand::uint32> MTRand::generateSeeds() {
259 <  // Seed the generator with an array from /dev/urandom if available
260 <  // Otherwise use a hash of time() and clock() values
258 >  inline void MTRand::seed( uint32 *const bigSeed, const uint32 seedLength )
259 >  {
260 >    // Seed the generator with an array of uint32's
261 >    // There are 2^19937-1 possible initial states.  This function allows
262 >    // all of those to be accessed by providing at least 19937 bits (with a
263 >    // default seed length of N = 624 uint32's).  Any bits above the lower 32
264 >    // in each element are discarded.
265 >    // Just call seed() if you want to get array from /dev/urandom
266 >    initialize(19650218UL);
267 >    register int i = 1;
268 >    register uint32 j = 0;
269 >    register int k = ( N > seedLength ? N : seedLength );
270 >    for( ; k; --k )
271 >      {
272 >        state[i] =
273 >          state[i] ^ ( (state[i-1] ^ (state[i-1] >> 30)) * 1664525UL );
274 >        state[i] += ( bigSeed[j] & 0xffffffffUL ) + j;
275 >        state[i] &= 0xffffffffUL;
276 >        ++i;  ++j;
277 >        if( i >= N ) { state[0] = state[N-1];  i = 1; }
278 >        if( j >= seedLength ) j = 0;
279 >      }
280 >    for( k = N - 1; k; --k )
281 >      {
282 >        state[i] =
283 >          state[i] ^ ( (state[i-1] ^ (state[i-1] >> 30)) * 1566083941UL );
284 >        state[i] -= i;
285 >        state[i] &= 0xffffffffUL;
286 >        ++i;
287 >        if( i >= N ) { state[0] = state[N-1];  i = 1; }
288 >      }
289 >    state[0] = 0x80000000UL;  // MSB is 1, assuring non-zero initial array
290 >    reload();
291 >  }
292  
312 –  std::vector<uint32> bigSeed;
293  
294 <  // First try getting an array from /dev/urandom
295 <  FILE* urandom = fopen( "/dev/urandom", "rb" );
296 <  if( urandom )
297 <    {
298 <      bigSeed.resize(N);
299 <      register uint32 *s = &bigSeed[0];
300 <      register int i = N;
301 <      register bool success = true;
302 <      while( success && i-- )
303 <        success = fread( s++, sizeof(uint32), 1, urandom );
324 <      fclose(urandom);
325 <      if( success ) { return bigSeed; }
294 >  inline void MTRand::seed()
295 >  {
296 >    std::vector<uint32> seeds;
297 >
298 >    seeds = generateSeeds();
299 >
300 >    if (seeds.size() == 1) {
301 >      seed( seeds[0] );
302 >    } else {
303 >      seed( &seeds[0], seeds.size() );
304      }
305 +  }
306 +
307 +
308 +  inline std::vector<MTRand::uint32> MTRand::generateSeeds() {
309 +    // Seed the generator with an array from /dev/urandom if available
310 +    // Otherwise use a hash of time() and clock() values
311 +
312 +    std::vector<uint32> bigSeed;
313 +
314 +    // First try getting an array from /dev/urandom
315 +    FILE* urandom = fopen( "/dev/urandom", "rb" );
316 +    if( urandom )
317 +      {
318 +        bigSeed.resize(N);
319 +        register uint32 *s = &bigSeed[0];
320 +        register int i = N;
321 +        register bool success = true;
322 +        while( success && i-- )
323 +          success = fread( s++, sizeof(uint32), 1, urandom );
324 +        fclose(urandom);
325 +        if( success ) { return bigSeed; }
326 +      }
327    
328 <  // Was not successful, so use time() and clock() instead
328 >    // Was not successful, so use time() and clock() instead
329  
330 <  bigSeed.push_back(hash( time(NULL), clock()));
331 <  return bigSeed;
332 < }
330 >    bigSeed.push_back(hash( time(NULL), clock()));
331 >    return bigSeed;
332 >  }
333  
334  
335 < inline void MTRand::initialize( const uint32 seed )
336 < {
337 <        // Initialize generator state with seed
338 <        // See Knuth TAOCP Vol 2, 3rd Ed, p.106 for multiplier.
339 <        // In previous versions, most significant bits (MSBs) of the seed affect
340 <        // only MSBs of the state array.  Modified 9 Jan 2002 by Makoto Matsumoto.
341 <        register uint32 *s = state;
342 <        register uint32 *r = state;
343 <        register int i = 1;
344 <        *s++ = seed & 0xffffffffUL;
345 <        for( ; i < N; ++i )
346 <        {
347 <                *s++ = ( 1812433253UL * ( *r ^ (*r >> 30) ) + i ) & 0xffffffffUL;
348 <                r++;
349 <        }
350 < }
335 >  inline void MTRand::initialize( const uint32 seed )
336 >  {
337 >    // Initialize generator state with seed
338 >    // See Knuth TAOCP Vol 2, 3rd Ed, p.106 for multiplier.
339 >    // In previous versions, most significant bits (MSBs) of the seed affect
340 >    // only MSBs of the state array.  Modified 9 Jan 2002 by Makoto Matsumoto.
341 >    register uint32 *s = state;
342 >    register uint32 *r = state;
343 >    register int i = 1;
344 >    *s++ = seed & 0xffffffffUL;
345 >    for( ; i < N; ++i )
346 >      {
347 >        *s++ = ( 1812433253UL * ( *r ^ (*r >> 30) ) + i ) & 0xffffffffUL;
348 >        r++;
349 >      }
350 >  }
351  
352  
353 < inline void MTRand::reload()
354 < {
355 <        // Generate N new values in state
356 <        // Made clearer and faster by Matthew Bellew (matthew.bellew@home.com)
357 <        register uint32 *p = state;
358 <        register int i;
359 <        for( i = N - M; i--; ++p )
360 <                *p = twist( p[M], p[0], p[1] );
361 <        for( i = M; --i; ++p )
362 <                *p = twist( p[M-N], p[0], p[1] );
363 <        *p = twist( p[M-N], p[0], state[0] );
353 >  inline void MTRand::reload()
354 >  {
355 >    // Generate N new values in state
356 >    // Made clearer and faster by Matthew Bellew (matthew.bellew@home.com)
357 >    register uint32 *p = state;
358 >    register int i;
359 >    for( i = N - M; i--; ++p )
360 >      *p = twist( p[M], p[0], p[1] );
361 >    for( i = M; --i; ++p )
362 >      *p = twist( p[M-N], p[0], p[1] );
363 >    *p = twist( p[M-N], p[0], state[0] );
364  
365 <        left = N, pNext = state;
366 < }
365 >    left = N, pNext = state;
366 >  }
367  
368  
369 < inline MTRand::uint32 MTRand::hash( time_t t, clock_t c )
370 < {
371 <        // Get a uint32 from t and c
372 <        // Better than uint32(x) in case x is floating point in [0,1]
373 <        // Based on code by Lawrence Kirby (fred@genesis.demon.co.uk)
369 >  inline MTRand::uint32 MTRand::hash( time_t t, clock_t c )
370 >  {
371 >    // Get a uint32 from t and c
372 >    // Better than uint32(x) in case x is floating point in [0,1]
373 >    // Based on code by Lawrence Kirby (fred@genesis.demon.co.uk)
374  
375 <        static uint32 differ = 0;  // guarantee time-based seeds will change
375 >    static uint32 differ = 0;  // guarantee time-based seeds will change
376  
377 <        uint32 h1 = 0;
378 <        unsigned char *p = (unsigned char *) &t;
379 <        for( size_t i = 0; i < sizeof(t); ++i )
380 <        {
381 <                h1 *= UCHAR_MAX + 2U;
382 <                h1 += p[i];
383 <        }
384 <        uint32 h2 = 0;
385 <        p = (unsigned char *) &c;
386 <        for( size_t j = 0; j < sizeof(c); ++j )
387 <        {
388 <                h2 *= UCHAR_MAX + 2U;
389 <                h2 += p[j];
390 <        }
391 <        return ( h1 + differ++ ) ^ h2;
392 < }
377 >    uint32 h1 = 0;
378 >    unsigned char *p = (unsigned char *) &t;
379 >    for( size_t i = 0; i < sizeof(t); ++i )
380 >      {
381 >        h1 *= UCHAR_MAX + 2U;
382 >        h1 += p[i];
383 >      }
384 >    uint32 h2 = 0;
385 >    p = (unsigned char *) &c;
386 >    for( size_t j = 0; j < sizeof(c); ++j )
387 >      {
388 >        h2 *= UCHAR_MAX + 2U;
389 >        h2 += p[j];
390 >      }
391 >    return ( h1 + differ++ ) ^ h2;
392 >  }
393  
394  
395 < inline void MTRand::save( uint32* saveArray ) const
396 < {
397 <        register uint32 *sa = saveArray;
398 <        register const uint32 *s = state;
399 <        register int i = N;
400 <        for( ; i--; *sa++ = *s++ ) {}
401 <        *sa = left;
402 < }
395 >  inline void MTRand::save( uint32* saveArray ) const
396 >  {
397 >    register uint32 *sa = saveArray;
398 >    register const uint32 *s = state;
399 >    register int i = N;
400 >    for( ; i--; *sa++ = *s++ ) {}
401 >    *sa = left;
402 >  }
403  
404  
405 < inline void MTRand::load( uint32 *const loadArray )
406 < {
407 <        register uint32 *s = state;
408 <        register uint32 *la = loadArray;
409 <        register int i = N;
410 <        for( ; i--; *s++ = *la++ ) {}
411 <        left = *la;
412 <        pNext = &state[N-left];
413 < }
405 >  inline void MTRand::load( uint32 *const loadArray )
406 >  {
407 >    register uint32 *s = state;
408 >    register uint32 *la = loadArray;
409 >    register int i = N;
410 >    for( ; i--; *s++ = *la++ ) {}
411 >    left = *la;
412 >    pNext = &state[N-left];
413 >  }
414  
415  
416 < inline std::ostream& operator<<( std::ostream& os, const MTRand& mtrand )
417 < {
418 <        register const MTRand::uint32 *s = mtrand.state;
419 <        register int i = mtrand.N;
420 <        for( ; i--; os << *s++ << "\t" ) {}
421 <        return os << mtrand.left;
422 < }
416 >  inline std::ostream& operator<<( std::ostream& os, const MTRand& mtrand )
417 >  {
418 >    register const MTRand::uint32 *s = mtrand.state;
419 >    register int i = mtrand.N;
420 >    for( ; i--; os << *s++ << "\t" ) {}
421 >    return os << mtrand.left;
422 >  }
423  
424  
425 < inline std::istream& operator>>( std::istream& is, MTRand& mtrand )
426 < {
427 <        register MTRand::uint32 *s = mtrand.state;
428 <        register int i = mtrand.N;
429 <        for( ; i--; is >> *s++ ) {}
430 <        is >> mtrand.left;
431 <        mtrand.pNext = &mtrand.state[mtrand.N-mtrand.left];
432 <        return is;
433 < }
425 >  inline std::istream& operator>>( std::istream& is, MTRand& mtrand )
426 >  {
427 >    register MTRand::uint32 *s = mtrand.state;
428 >    register int i = mtrand.N;
429 >    for( ; i--; is >> *s++ ) {}
430 >    is >> mtrand.left;
431 >    mtrand.pNext = &mtrand.state[mtrand.N-mtrand.left];
432 >    return is;
433 >  }
434  
435   }
436   #endif  // MERSENNETWISTER_H

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