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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


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

indicates floating-point rounding modes
gets or sets rounding direction
floating-point rounding direction
(macro constant)