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39 lines
1.3 KiB
C
39 lines
1.3 KiB
C
/*-------------------------------------------------------------------------
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*
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* geqo_random.h
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* random number generator
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*
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* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $PostgreSQL: pgsql/src/include/optimizer/geqo_random.h,v 1.18 2006/03/05 15:58:57 momjian Exp $
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*
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*-------------------------------------------------------------------------
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*/
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/* contributed by:
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=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
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* Martin Utesch * Institute of Automatic Control *
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= = University of Mining and Technology =
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* utesch@aut.tu-freiberg.de * Freiberg, Germany *
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=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=*=
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*/
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/* -- parts of this are adapted from D. Whitley's Genitor algorithm -- */
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#ifndef GEQO_RANDOM_H
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#define GEQO_RANDOM_H
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#include <math.h>
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/* geqo_rand returns a random float value between 0 and 1 inclusive */
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#define geqo_rand() ((double) random() / (double) MAX_RANDOM_VALUE)
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/* geqo_randint returns integer value between lower and upper inclusive */
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#define geqo_randint(upper,lower) \
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( (int) floor( geqo_rand()*(((upper)-(lower))+0.999999) ) + (lower) )
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#endif /* GEQO_RANDOM_H */
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