Limits on Floating-Point Constants

Microsoft Specific —>

Limits on the values of floating-point constants are given in Table 1.2. The header file FLOAT.H contains this information.

Table 1.2   Limits on Floating-Point Constants

Constant Meaning Value
FLT_DIG
DBL_DIG
LDBL_DIG
Number of digits, q, such that a floating-point number with q decimal digits can be rounded into a floating-point representation and back without loss of precision. 6
15
15
FLT_EPSILON
DBL_EPSILON
LDBL_EPSILON
Smallest positive number x, such that x + 1.0 is not equal to 1.0 1.192092896e–07F
2.2204460492503131e–016
2.2204460492503131e–016
FLT_GUARD 0
FLT_MANT_DIG
DBL_MANT_DIG
LDBL_MANT_DIG
Number of digits in the radix specified by FLT_RADIX in the floating-point significand. The radix is 2; hence these values specify bits. 24
53
53
FLT_MAX
DBL_MAX
LDBL_MAX
Maximum representable floating-point number. 3.402823466e+38F
1.7976931348623158e+308
1.7976931348623158e+308
FLT_MAX_10_EXP
DBL_MAX_10_EXP
LDBL_MAX_10_EXP
Maximum integer such that 10 raised to that number is a representable floating-point number. 38
308
308
FLT_MAX_EXP
DBL_MAX_EXP
LDBL_MAX_EXP
Maximum integer such that FLT_RADIX raised to that number is a representable floating-point number. 128
1024
1024
FLT_MIN
DBL_MIN
LDBL_MIN
Minimum positive value. 1.175494351e–38F
2.2250738585072014e–308
2.2250738585072014e–308
FLT_MIN_10_EXP
DBL_MIN_10_EXP
LDBL_MIN_10_EXP
Minimum negative integer such that 10 raised to that number is a representable floating-point number. –37
–307
–307
FLT_MIN_EXP
DBL_MIN_EXP
LDBL_MIN_EXP
Minimum negative integer such that FLT_RADIX raised to that number is a representable floating-point number. –125
–1021
–1021
FLT_NORMALIZE 0
FLT_RADIX
_DBL_RADIX
_LDBL_RADIX
Radix of exponent representation. 2
2
2
FLT_ROUNDS
_DBL_ROUNDS
_LDBL_ROUNDS
Rounding mode for floating-point addition. 1  (near)
1  (near)
1  (near)

Note that the information in Table 1.2 may differ in future implementations.

END Microsoft Specific