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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 |x| = 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 |n	- x/y| = 1/2
     then n is even.  Consequently the remainder is computed exactly and |r|
     <=	|y|/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	10.1			 June 20, 2004			  FreeBSD 10.1

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

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