static int test_random_numbers ( xd3_stream * stream , int ignore ) {
 usize_t i ;
 usize_t sum = 0 ;
 usize_t mean = 50 ;
 usize_t n_rounds = 1000000 ;
 double average , error ;
 double allowed_error = 0.1 ;
 mt_init ( & static_mtrand , 0x9f73f7fe ) ;
 for ( i = 0 ;
 i < n_rounds ;
 i += 1 ) {
 sum += mt_exp_rand ( mean , USIZE_T_MAX ) ;
 }
 average = ( double ) sum / ( double ) n_rounds ;
 error = average - ( double ) mean ;
 if ( error < allowed_error && error > - allowed_error ) {
 return 0 ;
 }
 stream -> msg = "random distribution looks broken" ;
 return XD3_INTERNAL ;
 }
static int test_random_numbers ( xd3_stream * stream , int ignore ) {
 usize_t i ;
 usize_t sum = 0 ;
 usize_t mean = 50 ;
 usize_t n_rounds = 1000000 ;
 double average , error ;
 double allowed_error = 0.1 ;
 mt_init ( & static_mtrand , 0x9f73f7fe ) ;
 for ( i = 0 ;
 i < n_rounds ;
 i += 1 ) {
 sum += mt_exp_rand ( mean , USIZE_T_MAX ) ;
 }
 average = ( double ) sum / ( double ) n_rounds ;
 error = average - ( double ) mean ;
 if ( error < allowed_error && error > - allowed_error ) {
 return 0 ;
 }
 stream -> msg = "random distribution looks broken" ;
 return XD3_INTERNAL ;
 }