logb, logbf, scalb, scalbf, significand, significandf - IEEE test functions
Math Library (libm, -lm)
#include <math.h>
double
logb(double x);
float
logbf(float x);
double
scalb(double x, double n);
float
scalbf(float x, float n);
double
significand(double x);
float
significandf(float x);
These functions allow users to test conformance to IEEE Std 754-1985.
Their use is not otherwise recommended.
logb(x) returns x's exponent n, a signed integer converted to double-precision
floating-point. logb(+-infinity) = +infinity; logb(0) = -infinity
with a division by zero exception.
scalbn(x, n) returns x*(2**n) computed by exponent manipulation.
significand(x) returns sig, where x := sig * 2**n with 1 <= sig < 2.
significand(x) is not defined when x is 0, +-infinity, or NaN.
ieee(3), math(3)
IEEE Std 754-1985
BSD March 10, 1994 BSD
[ Back ] |