Random Class Reference

Random class provides a set of Real and Integer linear congruential random operations. More...

#include <Random.h>

List of all members.

Public Member Functions
	Random (Integer a=16807, Integer b=0, Integer c=2147483647)
	Default constructor. Initialization constants from Park and Miller.
Integer	lCRandom ()
	Linear congruential method of random number generation. See Knuth, "Seminumerical Methods".
Real	random (Real L, Real U)
	Return a random value as a Real within a range of Reals.
Integer	random (Integer L, Integer U)
	Return a random value as a Real within a range of Reals.
Integer	seed (Integer s)
	Return old random seed, set new seed.
Integer	getTime ()
	Return number of seconds since epoch.

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Detailed Description

Random class provides a set of Real and Integer linear congruential random operations.

Note, this implementation does not produce very high-quality randomness. The methods here are good for understanding general principles, but for better numerical results see Press, et. al., "Numerical Recipes in C", Cambridge University Press, 1988.

Definition at line 29 of file Random.h.

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Constructor & Destructor Documentation

Random::Random	(	Integer	a = 16807,
		Integer	b = 0,
		Integer	c = 2147483647
	)			[inline]

Default constructor. Initialization constants from Park and Miller.

Definition at line 34 of file Random.h.

: m_a(a), m_b(b), m_c(c) { m_x = 1; }

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Member Function Documentation

Integer Random::getTime

(

)

Return number of seconds since epoch.

Used to automatically obtain fluctuating random sequences.

Returns:

Time in seconds since the epoch.

Definition at line 42 of file Random.cpp.

References Return.

Referenced by Time().

{
        Return( Integer(time(0)) );  // time_t
}

Integer Random::lCRandom

(

)

[inline]

Linear congruential method of random number generation. See Knuth, "Seminumerical Methods".

Definition at line 37 of file Random.h.

References If, and Return.

Referenced by LCRandom(), and random().

                            {
                m_x = mod( m_a * m_x + m_b, m_c );      // update x based on its previous value
                Integer r = m_x;
                If ( r < 0 )                                            // force the result to be positive                                                      
                        r = -r; 
                Return( r ); 
        }

Integer Random::random	(	Integer	L,
		Integer	U
	)			[inline]

Return a random value as a Real within a range of Reals.

Parameters:

	L	Lower bound
	U	Upper bound

Returns:

Random Integer value

Definition at line 59 of file Random.h.

References random(), and Return.

                                               {
                Real i = random( Real( L ), U + 1.0 );
                Return( Integer( i ) );
        }

Real Random::random	(	Real	L,
		Real	U
	)			[inline]

Return a random value as a Real within a range of Reals.

Parameters:

	L	Lower bound
	U	Upper bound

Returns:

Random Real value

Definition at line 49 of file Random.h.

References lCRandom(), and Return.

Referenced by IRandom(), Random(), and random().

                                      {
                Real r = lCRandom();
                r = r / Real( m_c );
                Return( r * ( U - L ) + L );
        }

Integer Random::seed

(

Integer

s

)

[inline]

Return old random seed, set new seed.

Parameters:

s

New Integer seed

Returns:

Old Integer seed

Definition at line 67 of file Random.h.

References Return.

Referenced by SeedRandom().

                                  {
                Integer r = m_x;
                m_x = s;
                Return( r );
        }

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The documentation for this class was generated from the following files:

• C:/Musimathics_local/Musimat/include/Random.h
• C:/Musimathics_local/Musimat/MusimatLib/Random.cpp

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