std::abs(float), std::fabs
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                    | Defined in header  <cmath> | ||
| float       abs( float arg ); | (1) | |
| double      abs( double arg ); | (2) | |
| long double abs( long double arg ); | (3) | |
| double      abs( Integral arg ); | (4) | (since C++11) | 
| float       fabs( float arg ); | (5) | |
| double      fabs( double arg ); | (6) | |
| long double fabs( long double arg ); | (7) | |
| double      fabs( Integral arg ); | (8) | (since C++11) | 
1-3,5-7) Computes the absolute value of a floating point value 
arg.4,8) A set of overloads or a function template for all combinations of arguments of arithmetic type not covered by (1-3,5-7). If any argument has integral type, it is cast to double. If any other argument is long double, then the return type is long double, otherwise it is double.
| Contents | 
[edit] Parameters
| arg | - | Value of a floating-point or Integral type | 
[edit] Return value
If successful, returns the absolute value of arg (|arg|). The value returned is exact and does not depend on any rounding modes.
[edit] Error handling
This function is not subject to any of the error conditions specified in math_errhandling
If the implementation supports IEEE floating-point arithmetic (IEC 60559),
- If the argument is ±0, +0 is returned
- If the argument is ±∞, +∞ is returned
- If the argument is NaN, NaN is returned
[edit] Notes
The overloads of std::abs for integer types (4) disagree in return types with the integer overloads of std::abs defined in <cstdlib>, and they also introduce the dangerous overloads of std::abs for unsigned integer types (Defect reports LWG 2192 and LWG 2294)
[edit] Example
Run this code
Possible output:
abs(+3.0) = 3 abs(-3.0) = 3 abs(-0.0) = 0 abs(-Inf) = inf
[edit] See also
| (C++11) | computes absolute value of an integral value (|x|) (function) | 
| (C++11) | copies the sign of a floating point value (function) | 
| (C++11) | checks if the given number is negative (function) | 
| returns the magnitude of a complex number (function template) | |
| applies the function std::abs to each element of valarray (function template) | |
| C documentation for fabs | |


