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IEEE(3)                FreeBSD Library Functions Manual                IEEE(3)

NAME
     copysign, copysignf, copysignl, finite, finitef, ilogb, ilogbf,
     nextafter, nextafterf, remainder, remainderf, scalbln, scalblnf, scalbn,
     scalbnf - functions for IEEE arithmetic

LIBRARY
     Math Library (libm, -lm)

SYNOPSIS
     #include <math.h>

     double
     copysign(double x, double y);

     float
     copysignf(float x, float y);

     long double
     copysignl(long double x, long double y);

     int
     finite(double x);

     int
     finitef(float x);

     int
     ilogb(double x);

     int
     ilogbf(float x);

     double
     nextafter(double x, double y);

     float
     nextafterf(float x, float y);

     double
     remainder(double x, double y);

     float
     remainderf(float x, float y);

     double
     scalbln(double x, long n);

     float
     scalblnf(float x, long n);

     double
     scalbn(double x, int n);

     float
     scalbnf(float x, int n);

DESCRIPTION
     These functions are required or recommended by IEEE Std 754-1985.

     The copysign(), copysignf() and copysignl() functions return x with its
     sign changed to y's.

     finite() and finitef() return the value 1 just when -infinity < x <
     +infinity; otherwise a zero is returned (when *(Bax*(Ba = infinity or x
     is NaN).

     ilogb() and ilogbf() return x's exponent, in integer format.
     ilogb(+-infinity) returns INT_MAX, ilogb(+-NaN) returns FP_ILOGBNAN and
     ilogb(0) returns FP_ILOGB0.

     nextafter() and nextafterf() return the next machine representable number
     from x in direction y.

     remainder() and remainderf() return the remainder r := x - n*y where n is
     the integer nearest the exact value of x/y; moreover if *(Ban - x/y*(Ba =
     1/2 then n is even.  Consequently the remainder is computed exactly and
     *(Bar*(Ba <= *(Bay*(Ba/2.  But remainder(x, 0) and remainder(infinity, 0)
     are invalid operations that produce a NaN.

     scalbln(), scalblnf(), scalbn(), and scalbnf() return x*(2**n) computed
     by exponent manipulation.

SEE ALSO
     math(3)

HISTORY
     The ieee functions appeared in 4.3BSD.  The copysignl(), scalbln(), and
     scalblnf() functions first appeared in FreeBSD 5.3.

STANDARDS
     IEEE Std 754-1985

FreeBSD 11.0-PRERELEASE          June 20, 2004         FreeBSD 11.0-PRERELEASE

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | SEE ALSO | HISTORY | STANDARDS

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