It uses the Mersenne Twister PRNG, which was originally developed by Makoto Matsumoto and Takuji Nishimura. Further information can be found at www.math.keio.ac.jp/~matumoto/emt.html. If you just need a random number, you simply call the g_random_* functions, which will create a globally used GRand and use the according g_rand_* functions internally. Whenever you need a stream of reproducible random numbers, you better create a GRand yourself and use the g_rand_* functions directly, which will also be slightly faster. Initializing a GRand with a certain seed will produce exactly the same series of random numbers on all platforms. This can thus be used as a seed for e.g. games. The g_rand*_range functions will return high quality equally distributed random numbers, whereas for example the (g_random_int()max) approach often doesn't yield equally distributed numbers. GLib changed the seeding algorithm for the pseudo-random number generator Mersenne Twister, as used by GRand and GRandom. This was necessary, because some seeds would yield very bad pseudo-random streams. Also the pseudo-random integers generated by g_rand*_int_range() will have a slightly better equal distribution with the new version of GLib. The original seeding and generation algorithms, as found in GLib 2.0.x, can be used instead of the new ones by setting the environment variable G_RANDOM_VERSION to the value of '2.0'. Use the GLib-2.0 algorithms only if you have sequences of numbers generated with Glib-2.0 that you need to reproduce exactly.
Public Member Functions | |
GRand * | getRandGStruct () |
this (GRand *gRand) | |
Sets our main struct and passes it to the parent class. | |
RandG | randCopy () |
Copies a GRand into a new one with the same exact state as before. | |
void | randFree () |
Frees the memory allocated for the GRand. | |
void | randSetSeed (uint seed) |
Sets the seed for the random number generator GRand to seed. | |
void | randSetSeedArray (uint *seed, uint seedLength) |
Initializes the random number generator by an array of longs. | |
uint | randInt () |
Returns the next random guint32 from rand_ equally distributed over the range [0. | |
int | randIntRange (int begin, int end) |
Returns the next random gint32 from rand_ equally distributed over the range [begin. | |
double | randDouble () |
Returns the next random gdouble from rand_ equally distributed over the range [0. | |
double | randDoubleRange (double begin, double end) |
Returns the next random gdouble from rand_ equally distributed over the range [begin. | |
Static Public Member Functions | |
static RandG | randNewWithSeed (uint seed) |
Creates a new random number generator initialized with seed. | |
static RandG | randNewWithSeedArray (uint *seed, uint seedLength) |
Creates a new random number generator initialized with seed. | |
static RandG | randNew () |
Creates a new random number generator initialized with a seed taken either from /dev/urandom (if existing) or from the current time (as a fallback). | |
static void | randomSetSeed (uint seed) |
Sets the seed for the global random number generator, which is used by the g_random_* functions, to seed. | |
static uint | randomInt () |
Return a random guint32 equally distributed over the range [0. | |
static int | randomIntRange (int begin, int end) |
Returns a random gint32 equally distributed over the range [begin. | |
static double | randomDouble () |
Returns a random gdouble equally distributed over the range [0. | |
static double | randomDoubleRange (double begin, double end) |
Returns a random gdouble equally distributed over the range [begin. | |
Protected Member Functions | |
void * | getStruct () |
the main Gtk struct as a void* | |
Protected Attributes | |
GRand * | gRand |
the main Gtk struct |
glib.RandG.RandG.this | ( | GRand * | gRand | ) |
Sets our main struct and passes it to the parent class.
GRand* glib.RandG.RandG.getRandGStruct | ( | ) |
void* glib.RandG.RandG.getStruct | ( | ) | [protected] |
the main Gtk struct as a void*
RandG glib.RandG.RandG.randCopy | ( | ) |
Copies a GRand into a new one with the same exact state as before.
This way you can take a snapshot of the random number generator for replaying later. rand_: a GRand. Returns: the new GRand. Since 2.4
double glib.RandG.RandG.randDouble | ( | ) |
Returns the next random gdouble from rand_ equally distributed over the range [0.
.1). rand_: a GRand. Returns: A random number.
double glib.RandG.RandG.randDoubleRange | ( | double | begin, | |
double | end | |||
) |
Returns the next random gdouble from rand_ equally distributed over the range [begin.
.end). rand_: a GRand. begin: lower closed bound of the interval. end: upper open bound of the interval. Returns: A random number.
void glib.RandG.RandG.randFree | ( | ) |
Frees the memory allocated for the GRand.
rand_: a GRand.
uint glib.RandG.RandG.randInt | ( | ) |
Returns the next random guint32 from rand_ equally distributed over the range [0.
.2^32-1]. rand_: a GRand. Returns: A random number.
Returns the next random gint32 from rand_ equally distributed over the range [begin.
.end-1]. rand_: a GRand. begin: lower closed bound of the interval. end: upper open bound of the interval. Returns: A random number.
static RandG glib.RandG.RandG.randNew | ( | ) | [static] |
Creates a new random number generator initialized with a seed taken either from /dev/urandom (if existing) or from the current time (as a fallback).
Returns: the new GRand.
Creates a new random number generator initialized with seed.
seed: a value to initialize the random number generator. Returns: the new GRand.
Creates a new random number generator initialized with seed.
seed: an array of seeds to initialize the random number generator. seed_length: an array of seeds to initialize the random number generator. Returns: the new GRand. Since 2.4
static double glib.RandG.RandG.randomDouble | ( | ) | [static] |
Returns a random gdouble equally distributed over the range [0.
.1). Returns: A random number.
static double glib.RandG.RandG.randomDoubleRange | ( | double | begin, | |
double | end | |||
) | [static] |
Returns a random gdouble equally distributed over the range [begin.
.end). begin: lower closed bound of the interval. end: upper open bound of the interval. Returns: A random number.
static uint glib.RandG.RandG.randomInt | ( | ) | [static] |
Return a random guint32 equally distributed over the range [0.
.2^32-1]. Returns: A random number.
Returns a random gint32 equally distributed over the range [begin.
.end-1]. begin: lower closed bound of the interval. end: upper open bound of the interval. Returns: A random number.
static void glib.RandG.RandG.randomSetSeed | ( | uint | seed | ) | [static] |
Sets the seed for the global random number generator, which is used by the g_random_* functions, to seed.
seed: a value to reinitialize the global random number generator.
void glib.RandG.RandG.randSetSeed | ( | uint | seed | ) |
Sets the seed for the random number generator GRand to seed.
rand_: a GRand. seed: a value to reinitialize the random number generator.
Initializes the random number generator by an array of longs.
Array can be of arbitrary size, though only the first 624 values are taken. This function is useful if you have many low entropy seeds, or if you require more then 32bits of actual entropy for your application. rand_: a GRand. seed: array to initialize with seed_length: length of array Since 2.4
GRand* glib.RandG.RandG.gRand [protected] |
the main Gtk struct