uclibc-ng/libm/float/powtst.c

#include <stdio.h>
#include <math.h>
extern float MAXNUMF, MAXLOGF, MINLOGF;

int
main()
{
float exp1, minnum, x, y, z, e;
exp1 = expf(1.0F);

minnum = powif(2.0F,-149);

x = exp1;
y = MINLOGF + logf(0.501);
/*y = MINLOGF - 0.405;*/
z = powf(x,y);
e = (z - minnum) / minnum;
printf("%.16e %.16e\n", z, e);

x = exp1;
y = MAXLOGF;
z = powf(x,y);
e = (z - MAXNUMF) / MAXNUMF;
printf("%.16e %.16e\n", z, e);

x = MAXNUMF;
y = 1.0F/MAXLOGF;
z = powf(x,y);
e = (z - exp1) / exp1;
printf("%.16e %.16e\n", z, e);


x = exp1;
y = MINLOGF;
z = powf(x,y);
e = (z - minnum) / minnum;
printf("%.16e %.16e\n", z, e);


exit(0);
}