/* step */
void random_step(ubx_block_t *b)
{
unsigned int rand_val;
struct rnd_info* inf;
inf=(struct rnd_info*) b->private_data;
ubx_port_t* rand_port = ubx_port_get(b, "rnd");
rand_val = random();
rand_val = (rand_val > inf->info.max) ? (rand_val%inf->info.max) : rand_val;
rand_val = (rand_val < inf->info.min) ? ((inf->info.min + rand_val)%inf->info.max) : rand_val;
write_rnd(rand_port, &rand_val);
}
int
gsl_ieee_set_mode (int precision, int rounding, int exception_mask)
{
unsigned long int mode = 0 ;
unsigned int rnd = 0 ;
/* I'm actually not completely sure that the alpha only supports default
* precisions rounding, but I couldn't find any information regarding this, so
* it seems safe to assume this for now until it's proven otherwise.
*/
switch (precision)
{
case GSL_IEEE_SINGLE_PRECISION:
GSL_ERROR ("Tru64 Unix on the alpha only supports default precision rounding",
GSL_EUNSUP) ;
break ;
case GSL_IEEE_DOUBLE_PRECISION:
GSL_ERROR ("Tru64 Unix on the alpha only supports default precision rounding",
GSL_EUNSUP) ;
break ;
case GSL_IEEE_EXTENDED_PRECISION:
GSL_ERROR ("Tru64 Unix on the alpha only supports default precision rounding",
GSL_EUNSUP) ;
break ;
}
switch (rounding)
{
case GSL_IEEE_ROUND_TO_NEAREST:
rnd = FP_RND_RN ;
write_rnd (rnd) ;
break ;
case GSL_IEEE_ROUND_DOWN:
rnd = FP_RND_RM ;
write_rnd (rnd) ;
break ;
case GSL_IEEE_ROUND_UP:
rnd = FP_RND_RP ;
write_rnd (rnd) ;
break ;
case GSL_IEEE_ROUND_TO_ZERO:
rnd = FP_RND_RZ ;
write_rnd (rnd) ;
break ;
default:
rnd = FP_RND_RN ;
write_rnd (rnd) ;
}
/* Turn on all the exceptions apart from 'inexact' */
/* from the ieee(3) man page:
* IEEE_TRAP_ENABLE_INV -> Invalid operation
* IEEE_TRAP_ENABLE_DZE -> Divide by 0
* IEEE_TRAP_ENABLE_OVF -> Overflow
* IEEE_TRAP_ENABLE_UNF -> Underflow
* IEEE_TRAP_ENABLE_INE -> Inexact (requires special option to C compiler)
* IEEE_TRAP_ENABLE_DNO -> denormal operand
* Note: IEEE_TRAP_ENABLE_DNO is not supported on OSF 3.x or Digital Unix
* 4.0 - 4.0d(?).
* IEEE_TRAP_ENABLE_MASK -> mask of all the trap enables
* IEEE_MAP_DMZ -> map denormal inputs to zero
* IEEE_MAP_UMZ -> map underflow results to zero
*/
mode = IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE | IEEE_TRAP_ENABLE_OVF
| IEEE_TRAP_ENABLE_UNF ;
if (exception_mask & GSL_IEEE_MASK_INVALID)
mode &= ~ IEEE_TRAP_ENABLE_INV ;
if (exception_mask & GSL_IEEE_MASK_DENORMALIZED)
{
#ifdef IEEE_TRAP_ENABLE_DNO
mode &= ~ IEEE_TRAP_ENABLE_DNO ;
#else
GSL_ERROR ("Sorry, this version of Digital Unix does not support denormalized operands", GSL_EUNSUP) ;
#endif
}
if (exception_mask & GSL_IEEE_MASK_DIVISION_BY_ZERO)
mode &= ~ IEEE_TRAP_ENABLE_DZE ;
if (exception_mask & GSL_IEEE_MASK_OVERFLOW)
mode &= ~ IEEE_TRAP_ENABLE_OVF ;
if (exception_mask & GSL_IEEE_MASK_UNDERFLOW)
mode &= ~ IEEE_TRAP_ENABLE_UNF ;
if (exception_mask & GSL_IEEE_TRAP_INEXACT)
{
/* To implement this would require a special flag to the C
compiler which can cause degraded performance */
GSL_ERROR ("Sorry, GSL does not implement trap-inexact for Tru64 Unix on the alpha - see fp-tru64.c for details", GSL_EUNSUP) ;
/* In case you need to add it, the appropriate line would be
*
* mode |= IEEE_TRAP_ENABLE_INE ;
*
*/
}
else
{
mode &= ~ IEEE_TRAP_ENABLE_INE ;
}
ieee_set_fp_control (mode) ;
return GSL_SUCCESS ;
}
