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#include <u.h>
#include <libc.h>
double
hypot2(double p, double q)
{
return sqrt(p*p + q*q);
}
double
hypot3(double x, double y, double z)
{
return sqrt(x*x + y*y + z*z);
}
double
hypot3from2(double x, double y, double z)
{
return hypot(hypot(x, z), y);
}
void
usage(void)
{
fprint(2, "usage: hypotenuse x y z\n");
exits("usage");
}
void
main(int argc, char *argv[])
{
double x, y, z, r;
vlong t0, t;
if(argc < 4)
usage();
x = strtod(argv[1], nil);
y = strtod(argv[2], nil);
z = strtod(argv[3], nil);
/*print("\t2D\n");
t0 = nsec();
r = hypot2(x, y);
t = nsec();
print("1st method: %g (%lld ns)\n", r, t-t0);
t0 = nsec();
r = hypot(x, y);
t = nsec();
print("2nd method: %g (%lld ns)\n", r, t-t0);
print("\t3D\n");
t0 = nsec();
r = hypot3(x, y, z);
t = nsec();
print("1st method: %g (%lld ns)\n", r, t-t0);*/
t0 = nsec();
r = hypot3from2(x, y, z);
t = nsec();
print("2nd method: %g (%lld ns)\n", r, t-t0);
exits(0);
}
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