## 1 Typedef and constants

The following data type has been defined via `typedef`.

`__complex128`: `__float128`-based complex number

The following macros are defined, which give the numeric limits of the `__float128` data type.

`FLT128_MAX`: largest finite number
`FLT128_MIN`: smallest positive number with full precision
`FLT128_EPSILON`: difference between 1 and the next larger

  representable number

`FLT128_DENORM_MIN`: smallest positive denormalized number
`FLT128_MANT_DIG`: number of digits in the mantissa (bit precision)
`FLT128_MIN_EXP`: maximal negative exponent
`FLT128_MAX_EXP`: maximal positive exponent
`FLT128_DIG`: number of decimal digits in the mantissa
`FLT128_MIN_10_EXP`: maximal negative decimal exponent
`FLT128_MAX_10_EXP`: maximal positive decimal exponent

The following mathematical constants of type `__float128` are defined.

`M_Eq`: the constant e (Euler’s number)
`M_LOG2Eq`: binary logarithm of 2
`M_LOG10Eq`: common, decimal logarithm of 2
`M_LN2q`: natural logarithm of 2
`M_LN10q`: natural logarithm of 10
`M_PIq`: pi
`M_PI_2q`: pi divided by two
`M_PI_4q`: pi divided by four
`M_1_PIq`: one over pi
`M_2_PIq`: one over two pi
`M_2_SQRTPIq`: two over square root of pi
`M_SQRT2q`: square root of 2
`M_SQRT1_2q`: one over square root of 2