Fixed width integer types (e.g. uint32) in Python

问题

Certain mathematical operations, especially on data read from hardware drivers, can depend on fixed width of the data type. Example: bitwise shift. What is the Pythonic way of creating integer variables with fixed width (e.g. uint32, int16 etc.) that would overflow/shift accordingly?

回答1:

I would suggest the fixedint library. The classes in that library are named in the following convention:

[Mutable][U]Int<N>

So for your two examples, the classes would be

#    C++                 Python fixedint
 std::uint32                 UInt32
 std::uint16                 UInt16

This supports things like bit-shifting, etc

>>> a = fixedint.UInt32(14)
>>> a
UInt32(14)
>>> a << 2
UInt32(56)

回答2:

For interfacing with hardware we normally use the struct standard library - specifically struct.pack and struct.unpack not only are fixed widths handled but also endianess issues. See the python 2 or python 3 library manuals.

来源：https://stackoverflow.com/questions/31145143/fixed-width-integer-types-e-g-uint32-in-python