## 9.3.128 RANDOM_SEED ([SIZE] [, PUT] [, GET])

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

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