llrand.h File Reference

Information, functions, and typedefs for randomness. More...

#include <boost/random/lagged_fibonacci.hpp>
#include <boost/random/mersenne_twister.hpp>

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Typedefs
typedef boost::lagged_fibonacci607	LLRandLagFib607
	typedefs for good boost lagged fibonacci.
typedef boost::lagged_fibonacci2281	LLRandLagFib2281
typedef boost::mt11213b	LLRandMT19937
Functions
S32	ll_rand ()
	Generate a float from [0, RAND_MAX).
S32	ll_rand (S32 val)
	Generate a float from [0, val) or (val, 0].
F32	ll_frand ()
	Generate a float from [0, 1.0).
F32	ll_frand (F32 val)
	Generate a float from [0, val) or (val, 0].
F64	ll_drand ()
	Generate a double from [0, 1.0).
F64	ll_drand (F64 val)
	Generate a double from [0, val) or (val, 0].

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Detailed Description

Information, functions, and typedefs for randomness.

LicenseInfo

firstyear=2000&license=viewergpl

Copyright (c) 2000-2007, Linden Research, Inc.

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Definition in file llrand.h.

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Typedef Documentation

typedef boost::lagged_fibonacci2281 LLRandLagFib2281

lengh of cycle: 2^120,000 memory: 2281*sizeof(double) (about 17K)

Definition at line 114 of file llrand.h.

typedef boost::lagged_fibonacci607 LLRandLagFib607

typedefs for good boost lagged fibonacci.

See also:

boost::lagged_fibonacci

These generators will quickly generate doubles. Note the memory requirements, because they are somewhat high. I chose the smallest one, and one comparable in speed but higher periodicity without outrageous memory requirements. To use: LLRandLagFib607 foo((U32)time(NULL)); double bar = foo(); lengh of cycle: 2^32,000 memory: 607*sizeof(double) (about 5K)

Definition at line 108 of file llrand.h.

typedef boost::mt11213b LLRandMT19937

typedefs for a good boost mersenne twister implementation.

See also:

boost::mersenne_twister

This fairly quickly generates U32 values To use: LLRandMT19937 foo((U32)time(NULL)); U32 bar = foo();

lengh of cycle: 2^19,937-1 memory: about 2496 bytes

Definition at line 131 of file llrand.h.

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Function Documentation

F64 ll_drand

(

F64

val

)

Generate a double from [0, val) or (val, 0].

Definition at line 163 of file llrand.cpp.

References ll_internal_random_double().

F64 ll_drand

(

)

Generate a double from [0, 1.0).

Definition at line 158 of file llrand.cpp.

References ll_internal_random_double().

F32 ll_frand

(

F32

val

)

Generate a float from [0, val) or (val, 0].

Definition at line 143 of file llrand.cpp.

References ll_internal_random_float().

F32 ll_frand

(

)

Generate a float from [0, 1.0).

Definition at line 138 of file llrand.cpp.

References ll_internal_random_float().

S32 ll_rand

(

S32

val

)

Generate a float from [0, val) or (val, 0].

Definition at line 130 of file llrand.cpp.

References ll_internal_random_double(), and S32.

S32 ll_rand

(

)

Generate a float from [0, RAND_MAX).

Definition at line 125 of file llrand.cpp.

References ll_rand().

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