float.h in C Language

Created2024-05-26|Updated2024-11-03|C Tutorial

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The header file float.h defines various macros related to the floating-point types float, double, and long double, specifying their ranges and precision.

FLT_ROUNDS
This macro indicates the rounding direction used in floating-point addition. Its possible values are:
- -1: Undetermined.
- 0: Round towards zero.
- 1: Round to the nearest integer.
- 2: Round towards positive infinity.
- 3: Round towards negative infinity.
FLT_RADIX
This macro represents the base of the exponent in scientific notation, which is generally 2.
Maximum Values of Floating-Point Types
- FLT_MAX
- DBL_MAX
- LDBL_MAX
Minimum Positive Values of Floating-Point Types
- FLT_MIN
- DBL_MIN
- LDBL_MIN
Smallest Difference Representable Between Two Floating-Point Values (Machine Precision)
- FLT_EPSILON
- DBL_EPSILON
- LDBL_EPSILON
DECIMAL_DIG
This macro indicates the number of decimal digits that can be represented accurately.
FLT_EVAL_METHOD
This macro specifies how floating-point expressions are evaluated regarding type conversion. Its possible values are:
- -1: Undetermined.
- 0: Operations are performed in the current type.
- 1: Operations involving float and double use the range and precision of double.
- 2: All floating-point operations use the range and precision of long double.
Number of Bits in the Mantissa
- FLT_MANT_DIG
- DBL_MANT_DIG
- LDBL_MANT_DIG
Number of Decimal Digits in the Exponent
- FLT_DIG
- DBL_DIG
- LDBL_DIG
Minimum Negative Exponent in Scientific Notation
- FLT_MIN_EXP
- DBL_MIN_EXP
- LDBL_MIN_EXP
Minimum Decimal Exponent in Scientific Notation (Negative)
- FLT_MIN_10_EXP
- DBL_MIN_10_EXP
- LDBL_MIN_10_EXP
Maximum Exponent in Scientific Notation
- FLT_MAX_EXP
- DBL_MAX_EXP
- LDBL_MAX_EXP
Maximum Decimal Exponent in Scientific Notation
- FLT_MAX_10_EXP
- DBL_MAX_10_EXP
- LDBL_MAX_10_EXP

Author: Johnson Lin

Link: http://linjiangxiong.com/2024/05/26/c-language-lib-float-h/

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