Retrieves the current value of the seed used in the random number generators.

Synopsis

#include <imsls.h>

int imsls_random_seed_get ( )

Return Value

The value of the seed.

Description

Function imsls_random_seed_get retrieves the current value of the “seed” used in the random number generators. A reason for doing this would be to restart a simulation, using function imsls_random_seed_set to reset the seed.

Example

This example illustrates the statements required to restart a simulation using imsls_random_seed_get and imsls_random_seed_set. The example shows that restarting the sequence of random numbers at the value of the seed last generated is the same as generating the random numbers all at once.

#include <imsls.h>

 

#define     N_RANDOM     5

 

int main()

{

    int         seed = 123457;

    float      *r1, *r2, *r;

    

    imsls_random_seed_set(seed);

    r1 = imsls_f_random_uniform(N_RANDOM, 0);

    imsls_f_write_matrix ("First Group of Random Numbers", 1,

                           N_RANDOM, r1, 0);

    seed = imsls_random_seed_get();

 

    imsls_random_seed_set(seed);

    r2 = imsls_f_random_uniform(N_RANDOM, 0);

    imsls_f_write_matrix ("Second Group of Random Numbers", 1,

                           N_RANDOM, r2, 0);

 

    imsls_random_seed_set(123457);

    r = imsls_f_random_uniform(2*N_RANDOM, 0);

    imsls_f_write_matrix ("Both Groups of Random Numbers", 1,

                           2*N_RANDOM, r, 0);

}

Output

               First Group of Random Numbers

         1           2           3           4           5

    0.9662      0.2607      0.7663      0.5693      0.8448

 

              Second Group of Random Numbers

         1           2           3           4           5

    0.0443      0.9872      0.6014      0.8964      0.3809

 

                     Both Groups of Random Numbers

         1           2           3           4           5           6

    0.9662      0.2607      0.7663      0.5693      0.8448      0.0443

 

         7           8           9          10

    0.9872      0.6014      0.8964      0.3809

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