rand.h

00001 /**********************************************************************
00002 rand.h - Pseudo random number generator.
00003  
00004 Copyright (C) 1998-2001 by OpenEye Scientific Software, Inc.
00005 Some portions Copyright (C) 2001-2006 by Geoffrey R. Hutchison
00006  
00007 This file is part of the Open Babel project.
00008 For more information, see <http://openbabel.sourceforge.net/>
00009  
00010 This program is free software; you can redistribute it and/or modify
00011 it under the terms of the GNU General Public License as published by
00012 the Free Software Foundation version 2 of the License.
00013  
00014 This program is distributed in the hope that it will be useful,
00015 but WITHOUT ANY WARRANTY; without even the implied warranty of
00016 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00017 GNU General Public License for more details.
00018 ***********************************************************************/
00019 
00020 #ifndef RAND_H
00021 #define RAND_H
00022 
00023 #include <openbabel/babelconfig.h>
00024 
00025 namespace OpenBabel
00026 {
00027 
00028   //******************************************
00029   //*** Stuff for random number generation ***
00030   //******************************************
00031 
00034   typedef struct
00035   {
00036     unsigned int hi;
00037     unsigned int lo;
00038   }
00039   DoubleType;
00040 
00041   OBAPI void DoubleMultiply( unsigned int,unsigned int,DoubleType*);
00042   OBAPI void DoubleAdd( DoubleType*,unsigned int);
00043   OBAPI unsigned int DoubleModulus( DoubleType*,unsigned int);
00044 
00047 
00068   class OBAPI OBRandom
00069   {
00070     DoubleType d;
00071     unsigned int m,a,c;
00072     unsigned int p;
00073     unsigned int i;
00074     unsigned int x;
00075     bool OBRandomUseSysRand;
00076 
00077   public:
00079     OBRandom(bool useSys= false);
00081     void Seed(int seed)
00082     {
00083       x = seed;
00084     }
00088     void TimeSeed();
00090     int NextInt();
00092     double NextFloat();
00093   };
00094 
00095 } // end namespace OpenBabel
00096 
00097 #endif // RAND_H
00098