IRAND - The GNU Fortran Compiler
Description: The GNU Fortran Compiler

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### 8.131 `IRAND` — Integer pseudo-random number

Description:
  `IRAND(FLAG)` returns a pseudo-random number from a uniform distribution between 0 and a system-dependent limit (which is in most cases 2147483647). If FLAG is 0, the next number in the current sequence is returned; if FLAG is 1, the generator is restarted by `CALL SRAND(0)`; if FLAG has any other value, it is used as a new seed with `SRAND`.

  This intrinsic routine is provided for backwards compatibility with GNU Fortran 77. It implements a simple modulo generator as provided by `g77`. For new code, one should consider the use of RANDOM_NUMBER as it implements a superior algorithm.

Standard:
  GNU extension
Class:
  Function
Syntax:
  `RESULT = IRAND(I)`
Arguments:

  I | Shall be a scalar `INTEGER` of kind 4.

Return value:
  The return value is of `INTEGER(kind=4)` type.
Example:

                program test_irand
                  integer,parameter :: seed = 86456

                  call srand(seed)
                  print *, irand(), irand(), irand(), irand()
                  print *, irand(seed), irand(), irand(), irand()
                end program test_irand