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

Synopsis

#include <imsl.h>

int imsl_random_seed_get ( )

Return Value

The value of the seed.

Description

The function imsl_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 imsl_random_seed_set to reset the seed.

Example

This example illustrates the statements required to restart a simulation using imsl_random_seed_get and imsl_random_seed_set. Also, 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 <imsl.h>

#define     N_RANDOM     5

main()
{
    int         seed = 123457;
    float       *r1, *r2, *r;
    
    imsl_random_seed_set(seed);
    r1 = imsl_f_random_uniform(N_RANDOM, 0);
    imsl_f_write_matrix ("First Group of Random Numbers", 1,
                         N_RANDOM, r1, 0);
    seed = imsl_random_seed_get();

    imsl_random_seed_set(seed);
    r2 = imsl_f_random_uniform(N_RANDOM, 0);
    imsl_f_write_matrix ("Second Group of Random Numbers", 1,
                         N_RANDOM, r2, 0);

    imsl_random_seed_set(123457);
    r = imsl_f_random_uniform(2*N_RANDOM, 0);
    imsl_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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