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                                                             dgsrand(3C)



        _________________________________________________________________
        dgsrand                                                 function
        Specify starting number for the dg_rand and dg_rand1 functions.
        _________________________________________________________________


        Calling Sequence

        int m, dgsrand();
        (void) dgsrand(m);

        where m is of type int.


        Description

        Use the dg_srand function to specify a seed for the dg_rand and
        dg_rand1 functions; this function is Data General's version of
        the srand function. The seed is the number from which random
        number generation will begin.  If you change the seed for either
        dg_rand or dg_rand1, you change it for the other.  If you specify
        a positive seed, both functions will base the random numbers on
        the seed.  If you specify a negative or 0 seed, both functions
        will use the current time as the seed.

        The include file math.h defines this entry.


        Returns

        The dg_srand function returns the new seed value.


        Related Functions

        See also the dg_rand, srand, and dg_rand1 functions.


        Example

        /* Program test for the dg_srand() function */

        #include <math.h>

        int  seed, m, i = 0, c, dg_srand();
        short int dg_rand();

        main() {
            printf("Enter a seed:\n");
            scanf("%d", &seed);
            dg_srand(seed);



        DG/UX 4.00                                                 Page 1
               Licensed material--property of copyright holder(s)





                                                             dgsrand(3C)



            printf("How many numbers?\n");
            scanf("%d", &c);
            printf("%d random numbers using a seed = %d:\n\n",
                   c, seed);
            while (i < c) {
                printf("%d\n", m = dg_rand());
                i++;
            }
        }

        A call to the program test with entries 13 and 4 generates the
        output

        4 random numbers using a seed = 13:

        13338
        2308
        17310
        17096

        These numbers will vary.

































        DG/UX 4.00                                                 Page 2
               Licensed material--property of copyright holder(s)



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