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NAME

fabs(), fabsf() — absolute value functions

SYNOPSIS

#include <math.h>

double fabs(double x);

float fabsf(float x);

DESCRIPTION

The fabs() function returns the absolute value of x, |x|.

The fabsf() function is a float version of fabs(); it takes a float argument and returns a float result. To use this function, compile either with the default -Ae option or with the -Aa and -D_HPUX_SOURCE options.

The fabsf() function is not specified by any standard, but it is named in accordance with the conventions specified in the "Future Library Directions" section of the ANSI C standard.

To use these functions, make sure your program includes <math.h>, and link in the math library by specifying -lm on the compiler or linker command line.

RETURN VALUE

If x is ±INFINITY, fabs() returns +INFINITY.

If if x is NaN, fabs() returns NaN.

If the correct value after rounding would be smaller in magnitude than MINDOUBLE, fabs() returns zero.

ERRORS

No errors are defined.

STANDARDS CONFORMANCE

fabs(): SVID3, XPG4.2, ANSI C

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