| 1 | 
/********************************************************************** | 
| 2 | 
rand.cpp - Pseudo random number generator. | 
| 3 | 
  | 
| 4 | 
Copyright (C) 1998-2001 by OpenEye Scientific Software, Inc. | 
| 5 | 
Some portions Copyright (C) 2001-2005 by Geoffrey R. Hutchison | 
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  | 
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This file is part of the Open Babel project. | 
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For more information, see <http://openbabel.sourceforge.net/> | 
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  | 
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This program is free software; you can redistribute it and/or modify | 
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it under the terms of the GNU General Public License as published by | 
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the Free Software Foundation version 2 of the License. | 
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  | 
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This program is distributed in the hope that it will be useful, | 
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but WITHOUT ANY WARRANTY; without even the implied warranty of | 
| 16 | 
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
| 17 | 
GNU General Public License for more details. | 
| 18 | 
***********************************************************************/ | 
| 19 | 
 | 
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/* derived from sample.c | 
| 21 | 
 * Pseudo-Random Number Generator Generator | 
| 22 | 
 * Roger Sayle, Metaphorics LLC | 
| 23 | 
 * Version 1.2, September 1998 | 
| 24 | 
 */ | 
| 25 | 
 | 
| 26 | 
#include <stdlib.h> | 
| 27 | 
#include <stdio.h> | 
| 28 | 
#include <math.h> | 
| 29 | 
#include "mol.hpp" | 
| 30 | 
#include "vector3.hpp" | 
| 31 | 
#include "obutil.hpp" | 
| 32 | 
 | 
| 33 | 
#ifndef True | 
| 34 | 
#define True   1 | 
| 35 | 
#define False  0 | 
| 36 | 
#endif | 
| 37 | 
 | 
| 38 | 
#define IsEven(x) (((x)&1)==0) | 
| 39 | 
#define IsOdd(x)  (((x)&1)!=0) | 
| 40 | 
 | 
| 41 | 
#define BothEven(x,y) IsEven((x)|(y)) | 
| 42 | 
#define IsPrime(x)    (!IsEven((x))&&IsOddPrime((x))) | 
| 43 | 
 | 
| 44 | 
#define HiPart(x)   (x>>16) | 
| 45 | 
#define LoPart(x)   ((x)&0xffff) | 
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 | 
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/* The maximum number of unique prime factors of a 32 bit number */ | 
| 48 | 
/* 2*3*5*7*11*13*17*19*23*29 = 6469693230 > 2^32 = 4294967296    */ | 
| 49 | 
#define MAXFACT    10 | 
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 | 
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namespace OpenBabel | 
| 52 | 
{ | 
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#define MAXPRIMES  256 | 
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static int primes[MAXPRIMES] = { | 
| 55 | 
                                   1,    2,    3,    5,    7,   11,   13,   17,   19,   23, | 
| 56 | 
                                   29,   31,   37,   41,   43,   47,   53,   59,   61,   67, | 
| 57 | 
                                   71,   73,   79,   83,   89,   97,  101,  103,  107,  109, | 
| 58 | 
                                   113,  127,  131,  137,  139,  149,  151,  157,  163,  167, | 
| 59 | 
                                   173,  179,  181,  191,  193,  197,  199,  211,  223,  227, | 
| 60 | 
                                   229,  233,  239,  241,  251,  257,  263,  269,  271,  277, | 
| 61 | 
                                   281,  283,  293,  307,  311,  313,  317,  331,  337,  347, | 
| 62 | 
                                   349,  353,  359,  367,  373,  379,  383,  389,  397,  401, | 
| 63 | 
                                   409,  419,  421,  431,  433,  439,  443,  449,  457,  461, | 
| 64 | 
                                   463,  467,  479,  487,  491,  499,  503,  509,  521,  523, | 
| 65 | 
                                   541,  547,  557,  563,  569,  571,  577,  587,  593,  599, | 
| 66 | 
                                   601,  607,  613,  617,  619,  631,  641,  643,  647,  653, | 
| 67 | 
                                   659,  661,  673,  677,  683,  691,  701,  709,  719,  727, | 
| 68 | 
                                   733,  739,  743,  751,  757,  761,  769,  773,  787,  797, | 
| 69 | 
                                   809,  811,  821,  823,  827,  829,  839,  853,  857,  859, | 
| 70 | 
                                   863,  877,  881,  883,  887,  907,  911,  919,  929,  937, | 
| 71 | 
                                   941,  947,  953,  967,  971,  977,  983,  991,  997, 1009, | 
| 72 | 
                                   1013, 1019, 1021, 1031, 1033, 1039, 1049, 1051, 1061, 1063, | 
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                                   1069, 1087, 1091, 1093, 1097, 1103, 1109, 1117, 1123, 1129, | 
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                                   1151, 1153, 1163, 1171, 1181, 1187, 1193, 1201, 1213, 1217, | 
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                                   1223, 1229, 1231, 1237, 1249, 1259, 1277, 1279, 1283, 1289, | 
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                                   1291, 1297, 1301, 1303, 1307, 1319, 1321, 1327, 1361, 1367, | 
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                                   1373, 1381, 1399, 1409, 1423, 1427, 1429, 1433, 1439, 1447, | 
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                                   1451, 1453, 1459, 1471, 1481, 1483, 1487, 1489, 1493, 1499, | 
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                                   1511, 1523, 1531, 1543, 1549, 1553, 1559, 1567, 1571, 1579, | 
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                                   1583, 1597, 1601, 1607, 1609, 1613 | 
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                               }; | 
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 | 
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static unsigned int isqrt( unsigned int val ) | 
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{ | 
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    register unsigned int temp; | 
| 86 | 
    register unsigned int rem; | 
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    register int i,result; | 
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 | 
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    i = 16; | 
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    while( !(val&((unsigned int)3<<30)) && i ) | 
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    { | 
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        val <<= 2; | 
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        i--; | 
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    } | 
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 | 
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    if( i ) | 
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    { | 
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        rem = (val>>30)-1; | 
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        val <<= 2; | 
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        result = 1; | 
| 101 | 
        i--; | 
| 102 | 
 | 
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        while( i ) | 
| 104 | 
        { | 
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            rem = (rem<<2) | (val>>30); | 
| 106 | 
            result <<= 1; | 
| 107 | 
            val <<= 2; | 
| 108 | 
 | 
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            temp = result<<1; | 
| 110 | 
            if( rem > temp ) | 
| 111 | 
            { | 
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                rem -= temp|1; | 
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                result |= 1; | 
| 114 | 
            } | 
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            i--; | 
| 116 | 
        } | 
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        return result; | 
| 118 | 
    } | 
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    else | 
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        return 0; | 
| 121 | 
} | 
| 122 | 
 | 
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static int IsOddPrime( unsigned int x ) | 
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{ | 
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    register unsigned int root; | 
| 126 | 
    register unsigned int i; | 
| 127 | 
 | 
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    root = isqrt(x); | 
| 129 | 
    for( i=2; i<MAXPRIMES-1; i++ ) | 
| 130 | 
    { | 
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        if( (x%primes[i]) == 0 ) | 
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            return False; | 
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        if( (unsigned int) primes[i] >= root ) | 
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            return True; | 
| 135 | 
    } | 
| 136 | 
 | 
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    for( i=primes[MAXPRIMES-1]; i<=root; i+=2 ) | 
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        if( (x%i) == 0 ) | 
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            return False; | 
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    return True; | 
| 141 | 
} | 
| 142 | 
 | 
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static int RelativelyPrime( unsigned int x, unsigned int y ) | 
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{ | 
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    if( BothEven(x,y) ) | 
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        return False; | 
| 147 | 
 | 
| 148 | 
    if( IsEven(x) ) | 
| 149 | 
    { | 
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        do | 
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        { | 
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            x >>= 1; | 
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        } | 
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        while( IsEven(x) ); | 
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    } | 
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    else | 
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        while( IsEven(y) ) | 
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            y >>= 1; | 
| 159 | 
 | 
| 160 | 
    while( x != y ) | 
| 161 | 
    { | 
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        if( x > y ) | 
| 163 | 
        { | 
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            x -= y; | 
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            do | 
| 166 | 
            { | 
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                x >>= 1; | 
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            } | 
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            while( IsEven(x) ); | 
| 170 | 
        } | 
| 171 | 
        else if( x < y ) | 
| 172 | 
        { | 
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            y -= x; | 
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            do | 
| 175 | 
            { | 
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                y >>= 1; | 
| 177 | 
            } | 
| 178 | 
            while( IsEven(y) ); | 
| 179 | 
        } | 
| 180 | 
    } | 
| 181 | 
    return( x == 1 ); | 
| 182 | 
} | 
| 183 | 
 | 
| 184 | 
void DoubleAdd( DoubleType *x, unsigned int y ) | 
| 185 | 
{ | 
| 186 | 
    x->lo += y; | 
| 187 | 
    if( x->lo < y ) | 
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        x->hi++; | 
| 189 | 
} | 
| 190 | 
 | 
| 191 | 
void DoubleMultiply( unsigned int x, unsigned int y, DoubleType *z ) | 
| 192 | 
{ | 
| 193 | 
    register unsigned int x0, x1, x2, x3; | 
| 194 | 
    register unsigned int hx, lx; | 
| 195 | 
    register unsigned int hy, ly; | 
| 196 | 
 | 
| 197 | 
    hx = HiPart(x); | 
| 198 | 
    lx = LoPart(x); | 
| 199 | 
    hy = HiPart(y); | 
| 200 | 
    ly = LoPart(y); | 
| 201 | 
 | 
| 202 | 
    x0 = lx*ly; | 
| 203 | 
    x1 = lx*hy; | 
| 204 | 
    x2 = hx*ly; | 
| 205 | 
    x3 = hx*hy; | 
| 206 | 
 | 
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    x1 += HiPart(x0); | 
| 208 | 
    x1 += x2; | 
| 209 | 
    if( x1 < x2 ) | 
| 210 | 
        x3 += (1<<16); | 
| 211 | 
 | 
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    z->hi = HiPart(x1) + x3; | 
| 213 | 
    z->lo = (LoPart(x1)<<16) + LoPart(x0); | 
| 214 | 
} | 
| 215 | 
 | 
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static int LeadingZeros( unsigned int x ) | 
| 217 | 
{ | 
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    static int table[256] = { | 
| 219 | 
                                0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5, | 
| 220 | 
                                6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, | 
| 221 | 
                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, | 
| 222 | 
                                7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, | 
| 223 | 
                                8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, | 
| 224 | 
                                8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, | 
| 225 | 
                                8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, | 
| 226 | 
                                8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8 | 
| 227 | 
                            }; | 
| 228 | 
 | 
| 229 | 
    if( x >= (1<<16) ) | 
| 230 | 
    { | 
| 231 | 
        if( x >= (1<<24) ) | 
| 232 | 
        { | 
| 233 | 
            return  8-table[x>>24]; | 
| 234 | 
        } | 
| 235 | 
        else | 
| 236 | 
            return 16-table[x>>16]; | 
| 237 | 
    } | 
| 238 | 
    else if( x >= (1<<8) ) | 
| 239 | 
    { | 
| 240 | 
        return 24-table[x>>8]; | 
| 241 | 
    } | 
| 242 | 
    else | 
| 243 | 
        return 32-table[x]; | 
| 244 | 
} | 
| 245 | 
 | 
| 246 | 
unsigned int DoubleModulus( DoubleType *n,  unsigned int d ) | 
| 247 | 
{ | 
| 248 | 
    register unsigned int d1, d0; | 
| 249 | 
    register unsigned int r1, r0; | 
| 250 | 
    register unsigned int m,s; | 
| 251 | 
 | 
| 252 | 
    s = LeadingZeros(d); | 
| 253 | 
    if( s > 0 ) | 
| 254 | 
    { | 
| 255 | 
        d = d<<s; | 
| 256 | 
        n->hi = (n->hi<<s) | (n->lo>>(32-s)); | 
| 257 | 
        n->lo = n->lo << s; | 
| 258 | 
    } | 
| 259 | 
 | 
| 260 | 
    d1 = HiPart(d); | 
| 261 | 
    d0 = LoPart(d); | 
| 262 | 
 | 
| 263 | 
    m = ((unsigned int)(n->hi/d1)) * d0; | 
| 264 | 
    r1 = ((n->hi%d1)<<16) + HiPart(n->lo); | 
| 265 | 
    if( r1 < m ) | 
| 266 | 
    { | 
| 267 | 
        r1 += d; | 
| 268 | 
        if( (r1>=d) && (r1<m) ) | 
| 269 | 
            r1 += d; | 
| 270 | 
    } | 
| 271 | 
    r1 -= m; | 
| 272 | 
 | 
| 273 | 
    m = ((unsigned int)(r1/d1)) * d0; | 
| 274 | 
    r0 = ((r1%d1)<<16) + LoPart(n->lo); | 
| 275 | 
    if( r0 < m ) | 
| 276 | 
    { | 
| 277 | 
        r0 += d; | 
| 278 | 
        if( (r0>=d) && (r0<m) ) | 
| 279 | 
            r0 += d; | 
| 280 | 
    } | 
| 281 | 
    r0 -= m; | 
| 282 | 
 | 
| 283 | 
    return r0 >> s; | 
| 284 | 
} | 
| 285 | 
 | 
| 286 | 
static int DeterminePotency( unsigned int m, unsigned int a ) | 
| 287 | 
{ | 
| 288 | 
    auto DoubleType d; | 
| 289 | 
    register unsigned int k; | 
| 290 | 
    register unsigned int b; | 
| 291 | 
    register int s; | 
| 292 | 
 | 
| 293 | 
    b = a-1; | 
| 294 | 
    k = b; | 
| 295 | 
    s = 1; | 
| 296 | 
    while( (k!=0) && (s<100) ) | 
| 297 | 
    { | 
| 298 | 
        DoubleMultiply(k,b,&d); | 
| 299 | 
        k = DoubleModulus(&d,m); | 
| 300 | 
        s++; | 
| 301 | 
    } | 
| 302 | 
    return s; | 
| 303 | 
} | 
| 304 | 
 | 
| 305 | 
static int DetermineFactors( unsigned int x, unsigned int *factors ) | 
| 306 | 
{ | 
| 307 | 
    register unsigned int *ptr; | 
| 308 | 
    register unsigned int half; | 
| 309 | 
    register unsigned int i; | 
| 310 | 
 | 
| 311 | 
    half = x/2; | 
| 312 | 
    ptr = factors; | 
| 313 | 
    for( i=1; i<MAXPRIMES; i++ ) | 
| 314 | 
    { | 
| 315 | 
        if( (x%primes[i]) == 0 ) | 
| 316 | 
            *ptr++ = primes[i]; | 
| 317 | 
        if( (unsigned int)(primes[i]) >= half ) | 
| 318 | 
            return ptr-factors; | 
| 319 | 
    } | 
| 320 | 
 | 
| 321 | 
    for( i=primes[MAXPRIMES-1]+2; i<=half; i+=2 ) | 
| 322 | 
        if( IsOddPrime(i) && ((x%i)==0) ) | 
| 323 | 
            *ptr++ = i; | 
| 324 | 
    return ptr-factors; | 
| 325 | 
} | 
| 326 | 
 | 
| 327 | 
static unsigned int DetermineIncrement( unsigned int m ) | 
| 328 | 
{ | 
| 329 | 
    register unsigned int hi,lo; | 
| 330 | 
    register unsigned int half; | 
| 331 | 
    register unsigned int i; | 
| 332 | 
 | 
| 333 | 
    /* 1/2 + sqrt(3)/6 */ | 
| 334 | 
    hi = (int)floor(0.7886751345948*m+0.5); | 
| 335 | 
    if( RelativelyPrime(m,hi) ) | 
| 336 | 
        return hi; | 
| 337 | 
 | 
| 338 | 
    /* 1/2 - sqrt(3)/6 */ | 
| 339 | 
    lo = (int)floor(0.2113248654052*m+0.5); | 
| 340 | 
    if( RelativelyPrime(m,lo) ) | 
| 341 | 
        return lo; | 
| 342 | 
 | 
| 343 | 
    half = m/2; | 
| 344 | 
    for( i=1; i<half; i++ ) | 
| 345 | 
    { | 
| 346 | 
        if( RelativelyPrime(m,hi+i) ) | 
| 347 | 
            return hi+i; | 
| 348 | 
        if( RelativelyPrime(m,hi-i) ) | 
| 349 | 
            return hi-i; | 
| 350 | 
        if( RelativelyPrime(m,lo+i) ) | 
| 351 | 
            return lo+i; | 
| 352 | 
        if( RelativelyPrime(m,lo-i) ) | 
| 353 | 
            return lo-i; | 
| 354 | 
    } | 
| 355 | 
    return 1; | 
| 356 | 
} | 
| 357 | 
 | 
| 358 | 
int DetermineSequence( unsigned int m, unsigned int *pm, | 
| 359 | 
                       unsigned int *pa, | 
| 360 | 
                       unsigned int *pc ) | 
| 361 | 
{ | 
| 362 | 
    auto unsigned int fact[MAXFACT]; | 
| 363 | 
    register unsigned int a=0, c; | 
| 364 | 
    register unsigned int b; | 
| 365 | 
    register int pot,best; | 
| 366 | 
    register int count; | 
| 367 | 
    register int flag; | 
| 368 | 
    register int i; | 
| 369 | 
 | 
| 370 | 
    do | 
| 371 | 
    { | 
| 372 | 
        best = 0; | 
| 373 | 
 | 
| 374 | 
        count = DetermineFactors(m,fact); | 
| 375 | 
        if( (m&3) == 0 ) | 
| 376 | 
            fact[0] = 4; | 
| 377 | 
 | 
| 378 | 
#ifdef DEBUG | 
| 379 | 
 | 
| 380 | 
        printf("factors(%d):",m); | 
| 381 | 
#endif | 
| 382 | 
 | 
| 383 | 
        if( count ) | 
| 384 | 
        { | 
| 385 | 
#ifdef DEBUG | 
| 386 | 
            printf("%u",fact[0]); | 
| 387 | 
            for( i=1; i<count; i++ ) | 
| 388 | 
                printf(",%u",fact[i]); | 
| 389 | 
#endif | 
| 390 | 
 | 
| 391 | 
            for( b=m-2; b>0; b-- ) | 
| 392 | 
            { | 
| 393 | 
                flag = True; | 
| 394 | 
                for( i=0; i<count; i++ ) | 
| 395 | 
                    if( b%fact[i] ) | 
| 396 | 
                    { | 
| 397 | 
                        flag = False; | 
| 398 | 
                        break; | 
| 399 | 
                    } | 
| 400 | 
 | 
| 401 | 
                if( flag ) | 
| 402 | 
                { | 
| 403 | 
                    pot = DeterminePotency(m,b+1); | 
| 404 | 
                    if( pot > best ) | 
| 405 | 
                    { | 
| 406 | 
                        best = pot; | 
| 407 | 
                        a = b+1; | 
| 408 | 
                    } | 
| 409 | 
                } | 
| 410 | 
            } | 
| 411 | 
 | 
| 412 | 
#ifdef DEBUG | 
| 413 | 
            if( best ) | 
| 414 | 
                printf(" [%d]",best); | 
| 415 | 
#endif | 
| 416 | 
 | 
| 417 | 
        } | 
| 418 | 
#ifdef DEBUG | 
| 419 | 
        printf("\n"); | 
| 420 | 
#endif | 
| 421 | 
 | 
| 422 | 
        m++; | 
| 423 | 
    } | 
| 424 | 
    while( best < 3 ); | 
| 425 | 
    m--; | 
| 426 | 
 | 
| 427 | 
    c = DetermineIncrement(m); | 
| 428 | 
 | 
| 429 | 
    *pm = m; | 
| 430 | 
    *pa = a; | 
| 431 | 
    *pc = c; | 
| 432 | 
    return best; | 
| 433 | 
} | 
| 434 | 
 | 
| 435 | 
 | 
| 436 | 
void GenerateSequence( unsigned int p, unsigned int m, | 
| 437 | 
                       unsigned int a, unsigned int c ) | 
| 438 | 
{ | 
| 439 | 
    register unsigned int i; | 
| 440 | 
    register unsigned int x; | 
| 441 | 
    auto DoubleType d; | 
| 442 | 
 | 
| 443 | 
    x = 0;  /* seed */ | 
| 444 | 
    for( i=0; i<p; i++ ) | 
| 445 | 
    { | 
| 446 | 
        printf("%u\n",x); | 
| 447 | 
 | 
| 448 | 
        do | 
| 449 | 
        { | 
| 450 | 
            DoubleMultiply(a,x,&d); | 
| 451 | 
            DoubleAdd(&d,c); | 
| 452 | 
            x = DoubleModulus(&d,m); | 
| 453 | 
        } | 
| 454 | 
        while( x >= p ); | 
| 455 | 
    } | 
| 456 | 
} | 
| 457 | 
 | 
| 458 | 
//********************************************** | 
| 459 | 
//***** Member functions from Random class ***** | 
| 460 | 
//********************************************** | 
| 461 | 
 | 
| 462 | 
OBRandom::OBRandom(bool useSysRand) | 
| 463 | 
{ | 
| 464 | 
 | 
| 465 | 
    this->OBRandomUseSysRand= useSysRand; | 
| 466 | 
    p = 70092; | 
| 467 | 
    DetermineSequence(p,&m,&a,&c); | 
| 468 | 
    x = 0;  /* seed */ | 
| 469 | 
} | 
| 470 | 
 | 
| 471 | 
int OBRandom::NextInt() | 
| 472 | 
{ | 
| 473 | 
    if (OBRandomUseSysRand) | 
| 474 | 
    { | 
| 475 | 
        return(rand()); | 
| 476 | 
    } | 
| 477 | 
    do | 
| 478 | 
    { | 
| 479 | 
        DoubleMultiply(a,x,&d); | 
| 480 | 
        DoubleAdd(&d,c); | 
| 481 | 
        x = DoubleModulus(&d,m); | 
| 482 | 
    } | 
| 483 | 
    while( x >= p ); | 
| 484 | 
 | 
| 485 | 
    return(x); | 
| 486 | 
} | 
| 487 | 
 | 
| 488 | 
double OBRandom::NextFloat() | 
| 489 | 
{ | 
| 490 | 
 | 
| 491 | 
    if (OBRandomUseSysRand) | 
| 492 | 
    { | 
| 493 | 
        return(double(rand())/double(RAND_MAX)); | 
| 494 | 
    } | 
| 495 | 
    do | 
| 496 | 
    { | 
| 497 | 
        DoubleMultiply(a,x,&d); | 
| 498 | 
        DoubleAdd(&d,c); | 
| 499 | 
        x = DoubleModulus(&d,m); | 
| 500 | 
    } | 
| 501 | 
    while( x >= p ); | 
| 502 | 
 | 
| 503 | 
    return((double)x/p); | 
| 504 | 
} | 
| 505 | 
 | 
| 506 | 
void OBRandom::TimeSeed() | 
| 507 | 
{ | 
| 508 | 
#ifdef WIN32 | 
| 509 | 
    // for VC++ do it this way | 
| 510 | 
    time_t ltime; | 
| 511 | 
    time(<ime); | 
| 512 | 
    const long secs= long(ltime); | 
| 513 | 
    x= secs % p; | 
| 514 | 
    srand( (unsigned)time( NULL ) ); | 
| 515 | 
#else | 
| 516 | 
 | 
| 517 | 
    timeval time; | 
| 518 | 
    gettimeofday(&time,(struct timezone *)NULL); | 
| 519 | 
    x = (time.tv_usec%p); | 
| 520 | 
    srand( x ); | 
| 521 | 
#ifdef HAVE_SRANDDEV | 
| 522 | 
    sranddev(); | 
| 523 | 
#endif | 
| 524 | 
 | 
| 525 | 
#endif | 
| 526 | 
} | 
| 527 | 
 | 
| 528 | 
} //end namespace OpenBabel | 
| 529 | 
 | 
| 530 | 
//! \file rand.cpp | 
| 531 | 
//! \brief Pseudo random number generator. |