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) and logbf(x) return 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) and scalbnf(x, n) return x*(2**n) computed by exponent
manipulation.
significand(x) and significandf(x) return sig, where x := sig * 2**n with
1 <= sig < 2. significand(x) and significandf(x) are not defined when x
is 0, +-infinity, or NaN.
ieee(3), math(3)
IEEE Std 754-1985
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