fabs, fabsf, fabsl

Article
12/18/2017

The latest version of this topic can be found at fabs, fabsf, fabsl.

Calculates the absolute value of the floating-point argument.

Syntax

double fabs(   
   double x   
);  
float fabs(  
   float x   
); // C++ only  
long double fabs(  
   long double x  
); // C++ only  
float fabsf(   
   float x   
);  
long double fabsl(  
   long double x  
);

Parameters

x
Floating-point value.

Return Value

The fabs functions return the absolute value of the argument x. There is no error return.

Input	SEH Exception	Matherr Exception
± QNAN,IND	none	_DOMAIN

Remarks

C++ allows overloading, so you can call overloads of fabs if you include the <cmath> header. In a C program, fabs always takes and returns a double.

Requirements

Function	Required C header	Required C++ header
`fabs`, `fabsf`, `fabsl`	<math.h>	<cmath> or <math.h>

For additional compatibility information, see Compatibility in the Introduction.

Example

See the example for abs.