diff options
Diffstat (limited to 'numpy/lib/getlimits.py')
| -rw-r--r-- | numpy/lib/getlimits.py | 92 |
1 files changed, 86 insertions, 6 deletions
diff --git a/numpy/lib/getlimits.py b/numpy/lib/getlimits.py index cab741e2e..4c432c0e4 100644 --- a/numpy/lib/getlimits.py +++ b/numpy/lib/getlimits.py @@ -21,7 +21,46 @@ _convert_to_float = { } class finfo(object): - """ Machine limits for floating point types. + """ + Machine limits for floating point types. + + Attributes + ---------- + eps : floating point number of the appropriate type + The smallest representable number such that ``1.0 + eps != 1.0``. + epsneg : floating point number of the appropriate type + The smallest representable 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 0s 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 : floating point number of the appropriate type + The smallest-magnitude usable number. Parameters ---------- @@ -30,14 +69,18 @@ class finfo(object): See Also -------- - numpy.lib.machar.MachAr + numpy.lib.machar.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 + import times. These objects are cached, so calling ``finfo()`` repeatedly inside your functions is not a problem. + """ _finfo_cache = {} @@ -126,10 +169,47 @@ nexp =%(nexp)6s min= -max class iinfo: - """Limits for integer types. + """ + Machine limits for integer types. + + Attributes + ---------- + min : int + The smallest integer expressible by the type. + max : int + The largest integer expressible by the type. + + Parameters + ---------- + type : integer type, dtype, or instance + The kind of integer data type to get information about. + + See Also + -------- + finfo : The equivalent for floating point data types. + + Examples + -------- + With types: + + >>> ii16 = np.iinfo(np.int16) + >>> ii16.min + -32768 + >>> ii16.max + 32767 + >>> ii32 = np.iinfo(np.int32) + >>> ii32.min + -2147483648 + >>> ii32.max + 2147483647 + + With instances: - :Parameters: - type : integer type or instance + >>> ii32 = np.iinfo(np.int32(10)) + >>> ii32.min + -2147483648 + >>> ii32.max + 2147483647 """ |