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# numpy.finfo

class `numpy.``finfo`

  Machine limits for floating point types.

  Parameters: | dtype : float, dtype, or instance Kind of floating point data-type about which to get information.

  See also

  `MachAr`
    The implementation of the tests that produce this information.
  `iinfo`
    The equivalent for integer data types.

  Notes

  For developers of NumPy: do not instantiate this at the module level. The initial calculation of these parameters is expensive and negatively impacts import times. These objects are cached, so calling `finfo()` repeatedly inside your functions is not a problem.

  Attributes

  bits | (int) The number of bits occupied by the type.
  eps | (float) The smallest representable positive number such that `1.0 + eps != 1.0`. Type of eps is an appropriate floating point type.
  epsneg | (floating point number of the appropriate type) The smallest representable positive number such that `1.0 - epsneg != 1.0`.
  iexp | (int) The number of bits in the exponent portion of the floating point representation.
  machar | (MachAr) The object which calculated these parameters and holds more detailed information.
  machep | (int) The exponent that yields eps.
  max | (floating point number of the appropriate type) The largest representable number.
  maxexp | (int) The smallest positive power of the base (2) that causes overflow.
  min | (floating point number of the appropriate type) The smallest representable number, typically `-max`.
  minexp | (int) The most negative power of the base (2) consistent with there being no leading 0’s in the mantissa.
  negep | (int) The exponent that yields epsneg.
  nexp | (int) The number of bits in the exponent including its sign and bias.
  nmant | (int) The number of bits in the mantissa.
  precision | (int) The approximate number of decimal digits to which this kind of float is precise.
  resolution | (floating point number of the appropriate type) The approximate decimal resolution of this type, i.e., `10**-precision`.
  tiny | (float) The smallest positive usable number. Type of tiny is an appropriate floating point type.