Random Number Functions

Random Number Functions
getrandmax()
int getrandmax()
This function returns the largest value that rand() can return.
lcg_value()
double lcg_value()
This function returns a psuedo-random number in the range (0, 1) via a linear congruential algorithm with a period equal to (2^31 - 85)*(2^31 - 249).
mt_getrandmax()
int mt_getrandmax()
This function returns the largest value that mt_rand() can return.
mt_rand()
int mt_rand(int $iMin = 0, int $iMax = mt_getrandmax())
This function returns a generated random integer in the range from $iMin to $iMax, using the Mersenne Twister algorithm.
Argument	Description
int $iMin	This is the minimum value that can be generated.
int $iMax	This is the maximum value that can be generated.
mt_srand()
int mt_srand(int $iSeed = random_seed, int $iMode = MT_RAND_MT19937)
This function seeds the pseudo-random number generator for the Mersenne Twister generator that is used by mt_rand(). A seed is used to generate a specific consistent sequence of numbers. This is often useful for testing.
Argument	Description
int $iSeed	This is the seed value. If it is not set, a random value is used.
int $iMode	This helps define the method for generating random numbers.
rand()
int rand(int $iMin = 0, int $iMax = getrandmax())
This function returns a generated random integer in the range from $iMin to $iMax. It has been made an alias of mt_rand() in PHP 7.1.0.
Argument	Description
int $iMin	This is the minimum value that can be generated.
int $iMax	This is the maximum value that can be generated.
srand()
int srand(int $iSeed = random_seed)
This function seeds the pseudo-random number generator for rand(). A seed is used to generate a specific consistent sequence of numbers. This is often useful for testing. In PHP 7.1.0, this is an alias for mt_srand().
Argument	Description
int $iSeed	This is the seed value. If it is not set, a random value is used.