Description: | Changes or queries the seed (starting point) for the pseudorandom number generator used by RANDOM_NUMBER. | ||
Class: | Subroutine | ||
Arguments: | No more than one argument can be specified. If no argument is specified, a random number based on the date and time is assigned to the seed. The three optional arguments follow1: | ||
SIZE (opt) | Must be scalar and of type default integer. It is set to the number of integers (N) that the processor uses to hold the value of the seed. | ||
PUT (opt) | Must be a default integer array of rank one and size >= N. It is used to reset the seed value. | ||
GET (opt) | Must be a default integer array of rank one and size >= N. It is set to the current value of the seed. | ||
1 SIZE and GET are INTENT(OUT) arguments; PUT is an INTENT(IN) argument. For more information on INTENT, see Section 5.10. |
Examples
Consider the following:
CALL RANDOM_SEED ! Processor initializes the
! seed randomly from the date
! and time
CALL RANDOM_SEED (SIZE = M) ! Sets M to N
CALL RANDOM_SEED (PUT = SEED (1 : M)) ! Sets user seed
CALL RANDOM_SEED (GET = OLD (1 : M)) ! Reads current seed