Developer Guide and Reference

ID 767251
Date 10/31/2024
Public
Document Table of Contents

SRAND

Portability Subroutine: Seeds the random number generator used with IRAND and RAND.

Module

USE IFPORT

CALL SRAND (iseed)

iseed

(Input) INTEGER(4). Any value. The default value is 1.

SRAND seeds the random number generator used with IRAND and RAND. Calling SRAND is equivalent to calling IRAND or RAND with a new seed.

The same value for iseed generates the same sequence of random numbers. To vary the sequence, call SRAND with a different iseed value each time the program is executed.

Example


 !  How many random numbers out of 100 will be between .5 and .6?
    USE IFPORT
    ICOUNT = 0
    CALL SRAND(123)
    DO I = 1, 100
      X = RAND(0)
      IF ((X>.5).AND.(x<.6)) ICOUNT = ICOUNT + 1
    END DO
    WRITE(*,*) ICOUNT, "numbers between .5 and .6!"
    END