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GNU Info (libc.info)IEEE Floating PointIEEE Floating Point ................... Here is an example showing how the floating type measurements come out for the most common floating point representation, specified by the `IEEE Standard for Binary Floating Point Arithmetic (ANSI/IEEE Std 754-1985)'. Nearly all computers designed since the 1980s use this format. The IEEE single-precision float representation uses a base of 2. There is a sign bit, a mantissa with 23 bits plus one hidden bit (so the total precision is 24 base-2 digits), and an 8-bit exponent that can represent values in the range -125 to 128, inclusive. So, for an implementation that uses this representation for the `float' data type, appropriate values for the corresponding parameters are: FLT_RADIX 2 FLT_MANT_DIG 24 FLT_DIG 6 FLT_MIN_EXP -125 FLT_MIN_10_EXP -37 FLT_MAX_EXP 128 FLT_MAX_10_EXP +38 FLT_MIN 1.17549435E-38F FLT_MAX 3.40282347E+38F FLT_EPSILON 1.19209290E-07F Here are the values for the `double' data type: DBL_MANT_DIG 53 DBL_DIG 15 DBL_MIN_EXP -1021 DBL_MIN_10_EXP -307 DBL_MAX_EXP 1024 DBL_MAX_10_EXP 308 DBL_MAX 1.7976931348623157E+308 DBL_MIN 2.2250738585072014E-308 DBL_EPSILON 2.2204460492503131E-016 automatically generated by info2www version 1.2.2.9 |