sqlrand.h

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/* sqlrand.h (Random numbers) */

/***********************************************************************
*  This code is part of Statistics for MySQL.
*
*  Copyright (C) 2011 Heinrich Schuchardt (xypron.glpk@gmx.de)
*
*  Licensed under the Apache License, Version 2.0 (the "License");
*  you may not use this file except in compliance with the License.
*  You may obtain a copy of the License at
*
*      http://www.apache.org/licenses/LICENSE-2.0
*
*  Unless required by applicable law or agreed to in writing, software
*  distributed under the License is distributed on an "AS IS" BASIS,
*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*  See the License for the specific language governing permissions and
*  limitations under the License.
***********************************************************************/

#ifndef SQLRAND_H

#define SQLRAND_H 1

#define MT_LEN          624 
#define MT_IA           397 
#define MT_IB           (MT_LEN - MT_IA) 
#define UPPER_MASK      0x80000000       
#define LOWER_MASK      0x7FFFFFFF       
#define MATRIX_A        0x9908B0DF       
#define TWIST(b,i,j)    ((b)[i] & UPPER_MASK) | ((b)[j] & LOWER_MASK)

#define MAGIC(s)        (((s)&1)*MATRIX_A)

namespace sqlstat {

class MersenneTwister {

private:
public:
  static void deinit();
  static void init();
  static double nextDouble();
  static unsigned long random();
  static double gaussian();
};
}
#endif // SQLRAND_H