FLT_ROUNDS

 

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C numeric limits interface

FLT_ROUNDS

FLT_EVAL_METHOD (C++11)

 

Defined in header <cfloat>
#define FLT_ROUNDS /* implementation defined */

Specifies the current rounding direction of floating-point arithmetic operations.

Value	Explanation
-1	the default rounding direction is not known
0	toward zero; same meaning as FE_TOWARDZERO
1	to nearest; same meaning as FE_TONEAREST
2	towards positive infinity; same meaning as FE_UPWARD
3	towards negative infinity; same meaning as FE_DOWNWARD
other values	implementation-defined behavior

Notes

The rounding mode can be changed with std::fesetround and FLT_ROUNDS reflects that change.

The possible values of FLT_ROUNDS match the possible values of std::float_round_style, returned by std::numeric_limits::round_style.

See also

float_round_style	indicates floating-point rounding modes (enum)
fegetroundfesetround (C++11)(C++11)	gets or sets rounding direction (function)
FE_DOWNWARDFE_TONEARESTFE_TOWARDZEROFE_UPWARD (C++11)	floating-point rounding direction (macro constant)
C documentation for FLT_ROUNDS