- Float.h
The header float.h in the
C Standard Library for theC programming language contains macros that expand to various limits and parameters of the standard floating-point types.The macros, as defined on ISO 9899:1999 section 5.2.4.2.2, are:
* FLT_ROUNDS - indicates the rounding mode for floating-point addition, meaning::* -1 indeterminable;:* 0 toward zero;:* 1 to nearest;:* 2 toward positive infinity;:* 3 toward negative infinity;:* other value means implementation-defined rounding behaviour.
* FLT_EVAL_METHOD - determines the evaluation formats of expressions involving all floating types::* -1 indeterminable;:* 0 evaluate all operations and constants just to the precision of the type;:* 1 evaluate operations and constants of type float and double to the range and precision of the double type;:* 2 evaulate all operations and constants to the range and precision of the long double type;:* other value means implementation-defined behavior.
* FLT_RADIX - radix of exponent representation (at least 2).
* FLT_MANT_DIG, DBL_MANT_DIG, LDBL_MANT_DIG - number of digits in the floating-point significand.
* DECIMAL_DIG - (at least 10)
* FLT_DIG, DBL_DIG, LDBL_DIG - (at least 6, 10, 10)
* FLT_MIN_EXP, DBL_MIN_EXP, LDBL_MIN_EXP
* FLT_MIN_10_EXP, DBL_MIN_10_EXP, LDBL_MIN_10_EXP, (at least -37)
* FLT_MAX_EXP, DBL_MAX_EXP, LDBL_MAX_EXP
* FLT_MAX_10_EXP, DBL_MAX_10_EXP, LDBL_MAX_10_EXP (at least +37)
* FLT_MAX, DBL_MAX, LDBL_MAX - (at least 1E+37)
* FLT_EPSILON, DBL_EPSILON, LDBL_EPSILON - (at least 1E-5, 1E-9, 1E-9)
* FLT_MIN, DBL_MIN, LDBL_MIN - (at least 1E-37)
External links
* [http://www.cwi.nl/~steven/enquire.html Enquire] : A program for automatically generating float.h, and for checking that the values in an existing float.h are correct
*man|bd|float.h|SUS|floating types
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