| Geant4 Cross Reference |
1 // -*- C++ -*-
2 //
3 // -----------------------------------------------------------------------
4 // HEP Random
5 // --- HepJamesRandom ---
6 // class implementation file
7 // -----------------------------------------------------------------------
8 // This file is part of Geant4 (simulation toolkit for HEP).
9 //
10 // This algorithm implements the original universal random number generator
11 // as proposed by Marsaglia & Zaman in report FSU-SCRI-87-50 and coded
12 // in FORTRAN77 by Fred James as the RANMAR generator, part of the MATHLIB
13 // HEP library.
14
15 // =======================================================================
16 // Gabriele Cosmo - Created: 5th September 1995
17 // - Fixed a bug in setSeed(): 26th February 1996
18 // - Minor corrections: 31st October 1996
19 // - Added methods for engine status: 19th November 1996
20 // - Fixed bug in setSeeds(): 15th September 1997
21 // J.Marraffino - Added stream operators and related constructor.
22 // Added automatic seed selection from seed table and
23 // engine counter: 16th Feb 1998
24 // Ken Smith - Added conversion operators: 6th Aug 1998
25 // J. Marraffino - Remove dependence on hepString class 13 May 1999
26 // V. Innocente - changed pointers to indices 3 may 2000
27 // M. Fischler - In restore, checkFile for file not found 03 Dec 2004
28 // M. Fischler - Methods for distrib. instacne save/restore 12/8/04
29 // M. Fischler - split get() into tag validation and
30 // getState() for anonymous restores 12/27/04
31 // M. Fischler - Enforcement that seeds be non-negative
32 // (lest the sequence be non-random) 2/14/05
33 // M. Fischler - put/get for vectors of ulongs 3/14/05
34 // M. Fischler - State-saving using only ints, for portability 4/12/05
35 //
36 // =======================================================================
37
38 #include "CLHEP/Random/Random.h"
39 #include "CLHEP/Random/JamesRandom.h"
40 #include "CLHEP/Random/engineIDulong.h"
41 #include "CLHEP/Random/DoubConv.h"
42 #include "CLHEP/Utility/atomic_int.h"
43
44 #include <atomic>
45 #include <cmath>
46 #include <cstdlib>
47 #include <iostream>
48 #include <string.h> // for strcmp
49 #include <string>
50 #include <vector>
51
52 namespace CLHEP {
53
54 namespace {
55 // Number of instances with automatic seed selection
56 CLHEP_ATOMIC_INT_TYPE numberOfEngines(0);
57
58 // Maximum index into the seed table
59 const int maxIndex = 215;
60 }
61
62 static const int MarkerLen = 64; // Enough room to hold a begin or end marker.
63
64 std::string HepJamesRandom::name() const {return "HepJamesRandom";}
65
66 HepJamesRandom::HepJamesRandom(long seed)
67 : HepRandomEngine()
68 {
69 setSeed(seed,0);
70 setSeeds(&theSeed,0);
71 }
72
73 HepJamesRandom::HepJamesRandom() // 15 Feb. 1998 JMM
74 : HepRandomEngine()
75 {
76 long seeds[2];
77 long seed;
78
79 int numEngines = numberOfEngines++;
80 int cycle = std::abs(int(numEngines/maxIndex));
81 int curIndex = std::abs(int(numEngines%maxIndex));
82
83 long mask = ((cycle & 0x007fffff) << 8);
84 HepRandom::getTheTableSeeds( seeds, curIndex );
85 seed = seeds[0]^mask;
86 setSeed(seed,0);
87 setSeeds(&theSeed,0);
88 }
89
90 HepJamesRandom::HepJamesRandom(int rowIndex, int colIndex) // 15 Feb. 1998 JMM
91 : HepRandomEngine()
92 {
93 long seed;
94 long seeds[2];
95
96 int cycle = std::abs(int(rowIndex/maxIndex));
97 int row = std::abs(int(rowIndex%maxIndex));
98 int col = std::abs(int(colIndex%2));
99 long mask = ((cycle & 0x000007ff) << 20);
100 HepRandom::getTheTableSeeds( seeds, row );
101 seed = (seeds[col])^mask;
102 setSeed(seed,0);
103 setSeeds(&theSeed,0);
104 }
105
106 HepJamesRandom::HepJamesRandom(std::istream& is)
107 : HepRandomEngine()
108 {
109 is >> *this;
110 }
111
112 HepJamesRandom::~HepJamesRandom() {}
113
114 void HepJamesRandom::saveStatus( const char filename[] ) const
115 {
116 std::ofstream outFile( filename, std::ios::out ) ;
117
118 if (!outFile.bad()) {
119 outFile << "Uvec\n";
120 std::vector<unsigned long> v = put();
121 for (unsigned int i=0; i<v.size(); ++i) {
122 outFile << v[i] << "\n";
123 }
124 }
125 }
126
127 void HepJamesRandom::restoreStatus( const char filename[] )
128 {
129 int ipos, jpos;
130 std::ifstream inFile( filename, std::ios::in);
131 if (!checkFile ( inFile, filename, engineName(), "restoreStatus" )) {
132 std::cerr << " -- Engine state remains unchanged\n";
133 return;
134 }
135 if ( possibleKeywordInput ( inFile, "Uvec", theSeed ) ) {
136 std::vector<unsigned long> v;
137 unsigned long xin;
138 for (unsigned int ivec=0; ivec < VECTOR_STATE_SIZE; ++ivec) {
139 inFile >> xin;
140 if (!inFile) {
141 inFile.clear(std::ios::badbit | inFile.rdstate());
142 std::cerr << "\nJamesRandom state (vector) description improper."
143 << "\nrestoreStatus has failed."
144 << "\nInput stream is probably mispositioned now." << std::endl;
145 return;
146 }
147 v.push_back(xin);
148 }
149 getState(v);
150 return;
151 }
152
153 if (!inFile.bad() && !inFile.eof()) {
154 // inFile >> theSeed; removed -- encompased by possibleKeywordInput
155 for (int i=0; i<97; ++i)
156 inFile >> u[i];
157 inFile >> c; inFile >> cd; inFile >> cm;
158 inFile >> jpos;
159 ipos = (64+jpos)%97;
160 i97 = ipos;
161 j97 = jpos;
162 }
163 }
164
165 void HepJamesRandom::showStatus() const
166 {
167 std::cout << std::endl;
168 std::cout << "----- HepJamesRandom engine status -----" << std::endl;
169 std::cout << " Initial seed = " << theSeed << std::endl;
170 std::cout << " u[] = ";
171 for (int i=0; i<97; ++i)
172 std::cout << u[i] << " ";
173 std::cout << std::endl;
174 std::cout << " c = " << c << ", cd = " << cd << ", cm = " << cm
175 << std::endl;
176 std::cout << " i97 = " << i97 << ", u[i97] = " << u[i97] << std::endl;
177 std::cout << " j97 = " << j97 << ", u[j97] = " << u[j97] << std::endl;
178 std::cout << "----------------------------------------" << std::endl;
179 }
180
181 void HepJamesRandom::setSeed(long seed, int)
182 {
183 // The input value for "seed" should be within the range [0,900000000]
184 //
185 // Negative seeds result in serious flaws in the randomness;
186 // seeds above 900000000 are OK because of the %177 in the expression for i,
187 // but may have the same effect as other seeds below 900000000.
188
189 int m, n;
190 float s, t;
191 long mm;
192
193 if (seed < 0) {
194 std::cout << "Seed for HepJamesRandom must be non-negative\n"
195 << "Seed value supplied was " << seed
196 << "\nUsing its absolute value instead\n";
197 seed = -seed;
198 }
199
200 long ij = seed/30082;
201 long kl = seed - 30082*ij;
202 long i = (ij/177) % 177 + 2;
203 long j = ij % 177 + 2;
204 long k = (kl/169) % 178 + 1;
205 long l = kl % 169;
206
207 theSeed = seed;
208
209 for ( n = 1 ; n < 98 ; n++ ) {
210 s = 0.0;
211 t = 0.5;
212 for ( m = 1 ; m < 25 ; m++) {
213 mm = ( ( (i*j) % 179 ) * k ) % 179;
214 i = j;
215 j = k;
216 k = mm;
217 l = ( 53 * l + 1 ) % 169;
218 if ( (l*mm % 64 ) >= 32 )
219 s += t;
220 t *= 0.5;
221 }
222 u[n-1] = s;
223 }
224 c = 362436.0 / 16777216.0;
225 cd = 7654321.0 / 16777216.0;
226 cm = 16777213.0 / 16777216.0;
227
228 i97 = 96;
229 j97 = 32;
230
231 }
232
233 void HepJamesRandom::setSeeds(const long* seeds, int)
234 {
235 setSeed(seeds ? *seeds : 19780503L, 0);
236 theSeeds = seeds;
237 }
238
239 double HepJamesRandom::flat()
240 {
241 double uni;
242
243 do {
244 uni = u[i97] - u[j97];
245 if ( uni < 0.0 ) uni++;
246 u[i97] = uni;
247
248 if (i97 == 0) i97 = 96;
249 else i97--;
250
251 if (j97 == 0) j97 = 96;
252 else j97--;
253
254 c -= cd;
255 if (c < 0.0) c += cm;
256
257 uni -= c;
258 if (uni < 0.0) uni += 1.0;
259 } while ( uni <= 0.0 || uni >= 1.0 );
260
261 return uni;
262 }
263
264 void HepJamesRandom::flatArray(const int size, double* vect)
265 {
266 // double uni;
267 int i;
268
269 for (i=0; i<size; ++i) {
270 vect[i] = flat();
271 }
272 }
273
274 HepJamesRandom::operator double() {
275 return flat();
276 }
277
278 HepJamesRandom::operator float() {
279 return float( flat() );
280 }
281
282 HepJamesRandom::operator unsigned int() {
283 return ((unsigned int)(flat() * exponent_bit_32()) & 0xffffffff ) |
284 (((unsigned int)( u[i97] * exponent_bit_32())>>16) & 0xff);
285 }
286
287 std::ostream & HepJamesRandom::put ( std::ostream& os ) const {
288 char beginMarker[] = "JamesRandom-begin";
289 os << beginMarker << "\nUvec\n";
290 std::vector<unsigned long> v = put();
291 for (unsigned int i=0; i<v.size(); ++i) {
292 os << v[i] << "\n";
293 }
294 return os;
295 }
296
297 std::vector<unsigned long> HepJamesRandom::put () const {
298 std::vector<unsigned long> v;
299 v.push_back (engineIDulong<HepJamesRandom>());
300 std::vector<unsigned long> t;
301 for (int i=0; i<97; ++i) {
302 t = DoubConv::dto2longs(u[i]);
303 v.push_back(t[0]); v.push_back(t[1]);
304 }
305 t = DoubConv::dto2longs(c);
306 v.push_back(t[0]); v.push_back(t[1]);
307 t = DoubConv::dto2longs(cd);
308 v.push_back(t[0]); v.push_back(t[1]);
309 t = DoubConv::dto2longs(cm);
310 v.push_back(t[0]); v.push_back(t[1]);
311 v.push_back(static_cast<unsigned long>(j97));
312 return v;
313 }
314
315
316 std::istream & HepJamesRandom::get ( std::istream& is) {
317 char beginMarker [MarkerLen];
318 is >> std::ws;
319 is.width(MarkerLen); // causes the next read to the char* to be <=
320 // that many bytes, INCLUDING A TERMINATION \0
321 // (Stroustrup, section 21.3.2)
322 is >> beginMarker;
323 if (strcmp(beginMarker,"JamesRandom-begin")) {
324 is.clear(std::ios::badbit | is.rdstate());
325 std::cerr << "\nInput stream mispositioned or"
326 << "\nJamesRandom state description missing or"
327 << "\nwrong engine type found." << std::endl;
328 return is;
329 }
330 return getState(is);
331 }
332
333 std::string HepJamesRandom::beginTag ( ) {
334 return "JamesRandom-begin";
335 }
336
337 std::istream & HepJamesRandom::getState ( std::istream& is) {
338 if ( possibleKeywordInput ( is, "Uvec", theSeed ) ) {
339 std::vector<unsigned long> v;
340 unsigned long uu;
341 for (unsigned int ivec=0; ivec < VECTOR_STATE_SIZE; ++ivec) {
342 is >> uu;
343 if (!is) {
344 is.clear(std::ios::badbit | is.rdstate());
345 std::cerr << "\nJamesRandom state (vector) description improper."
346 << "\ngetState() has failed."
347 << "\nInput stream is probably mispositioned now." << std::endl;
348 return is;
349 }
350 v.push_back(uu);
351 }
352 getState(v);
353 return (is);
354 }
355
356 // is >> theSeed; Removed, encompassed by possibleKeywordInput()
357
358 int ipos, jpos;
359 char endMarker [MarkerLen];
360 for (int i=0; i<97; ++i) {
361 is >> u[i];
362 }
363 is >> c; is >> cd; is >> cm;
364 is >> jpos;
365 is >> std::ws;
366 is.width(MarkerLen);
367 is >> endMarker;
368 if(strcmp(endMarker,"JamesRandom-end")) {
369 is.clear(std::ios::badbit | is.rdstate());
370 std::cerr << "\nJamesRandom state description incomplete."
371 << "\nInput stream is probably mispositioned now." << std::endl;
372 return is;
373 }
374
375 ipos = (64+jpos)%97;
376 i97 = ipos;
377 j97 = jpos;
378 return is;
379 }
380
381 bool HepJamesRandom::get (const std::vector<unsigned long> & v) {
382 if ( (v[0] & 0xffffffffUL) != engineIDulong<HepJamesRandom>()) {
383 std::cerr <<
384 "\nHepJamesRandom get:state vector has wrong ID word - state unchanged\n";
385 return false;
386 }
387 return getState(v);
388 }
389
390 bool HepJamesRandom::getState (const std::vector<unsigned long> & v) {
391 if (v.size() != VECTOR_STATE_SIZE ) {
392 std::cerr <<
393 "\nHepJamesRandom get:state vector has wrong length - state unchanged\n";
394 return false;
395 }
396 std::vector<unsigned long> t(2);
397 for (int i=0; i<97; ++i) {
398 t[0] = v[2*i+1]; t[1] = v[2*i+2];
399 u[i] = DoubConv::longs2double(t);
400 }
401 t[0] = v[195]; t[1] = v[196]; c = DoubConv::longs2double(t);
402 t[0] = v[197]; t[1] = v[198]; cd = DoubConv::longs2double(t);
403 t[0] = v[199]; t[1] = v[200]; cm = DoubConv::longs2double(t);
404 j97 = (int)v[201];
405 i97 = (64+j97)%97;
406 return true;
407 }
408
409 } // namespace CLHEP
410