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#include <conf.h>
#include <stdio.h>
#include <stdlib.h>
#include <x_types.h>
#include <sys/types.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#ifdef HAVE_SYS_TIME_H
#ifdef TIME_WITH_SYS_TIME
#include <time.h>
#endif
#endif
#include <unistd.h>
Real64
drandom()
{
static Uns8 initialized = 0;
Int32 the_seed;
if(! initialized){
the_seed = (Int32) (time(NULL) * getpid());
#ifdef HAVE_GETTIMEOFDAY
{
struct timeval tv;
gettimeofday(&tv, NULL);
the_seed *= (tv.tv_sec * 1000 + tv.tv_usec / 1000
+ (tv.tv_usec % 1000) * 100000000);
}
#endif
#ifdef HAVE_DRAND48
srand48((long int) the_seed);
#else
#ifdef HAVE_RAND
srand((unsigned int) the_seed);
#endif
#endif
initialized = 1;
}
#ifdef HAVE_DRAND48
return((Real64) drand48());
#else
#ifdef HAVE_RAND
return((Real64) rand() / (Real64) (RAND_MAX));
#endif
#endif
#if !defined(HAVE_DRAND48) && !defined(HAVE_RAND)
#error "No random function found."
#endif
}
Real64
Real64_precision()
{
static Int16 prec_calculated = 0;
Real64 d, q;
static Real64 p;
if(prec_calculated)
return(p);
d = 1.0;
q = 2.0;
while(q != 1.0){
while(1.0 + d != 1.0){
p = d;
d /= q;
}
d = p;
q = 1.0 + ((q - 1.0) / 2.0);
}
prec_calculated = 1;
return(p);
}
double
r_int(double d)
{
int r;
r = (d > 0.0 ? (int) (d + 0.5) : - (int) (-d + 0.5));
return((double) r);
}
int
is_nan(float f)
{
char *u;
u = (char *) (&f);
if((u[3] & 127) == 127 && (u[2] & 128) == 128 &&
((u[2] & 127) != 0 || u[1] != 0 || u[0] != 0))
return(1);
return(0);
}
/************ end of $RCSfile$ ******************/
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