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
);

#define fabs(X) // Requires C11 or later

Parameters

x
Floating-point value.

Return value

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

Remarks

C++ allows overloading, so you can call overloads of fabs if you include the <cmath> header. In a C program, unless you're using the <tgmath.h> macro to call this function, fabs always takes and returns a double.

If you use the fabs macro from <tgmath.h>, the type of the argument determines which version of the function is selected. See Type-generic math for details.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Requirements

For more compatibility information, see Compatibility.

Example

See the example for abs.

See also

Math and floating-point support
abs, labs, llabs, _abs64
_cabs