Use of absolute value functions abs and FABS

Evaluate the absolute value of a number. Supported by library functions provided by VC ++, when it must include: # include <math. h>

There are several types: ABS, _ abs64, FABS, fabsf,Labs,_ Cabs. Details are as follows:

//Calculate the absolute value.

int abs(    int n );long abs(    long n );   // C++ onlydouble abs(    double n );   // C++ onlylong double abs(   long double n);   // C++ onlyfloat abs(   float n );   // C++ only__int64 _abs64(    __int64 n );
//Calculates the absolute value of the floating-point argument.
double fabs(    double x );float fabs(   float x ); // C++ onlylong double fabs(   long double x); // C++ onlyfloat fabsf(    float x );
//Calculates the absolute value of a long integer.
long labs(      long n );

//Calculates the absolute value of a complex number.
double _cabs(    struct _complex z );

The prototype of the above function is from msdn2008. It can be seen that there are many overloaded functions in ads. Generally, ADS () can meet the requirements (C ++). Other cases are special cases.
You can also use a template to redefine it.

Use of absolute value functions abs and FABS