Byte to integer conversion

[Christian Tismer]

Elefterios Stamatogiannakis wrote:
> 
>         How can i convert two, three, four bytes into an integer?

one byte is cheap with the ord function:

>>> ord("@")
64
>>> 

> 
>         I know a way with pickle, using loads() but i wonder is there
> a more elegant way of doing it.

There is the struct module which can do such stuff.

>>> import struct
>>> struct.unpack("b", "#")
(35,)
>>> struct.unpack("h", "xx")
(30840,)
>>> struct.unpack("i", "abcd")
(1684234849,)
>>> 

The three-byte case isn't handled there. If you are lazy
and just want it short, use

>>> arg="abc"
>>> struct.unpack("i", arg + "\0")
(6513249,)
>>> 

assuming little endian here of course.

>         I don't care about big, little endian problems

You should at least know it when you compute
your salary this way.

ciao - chris

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