trouble converting c++ bitshift to python equivalent

[Steve Holden]

nanodust at gmail.com wrote:
> hello all
> 
> i am relatively new to python, catching on, but getting stuck on
> simple thing:
> 
> i have two string bytes i need to push into a single (short) int, like
> so in c:
> 
>    temp = strBuf[2];
> 
>    temp = (temp<<7)+(strBuf[1]);
> 
> c code works, but having trouble getting python to perform same
> function!
> 
> keep getting type & operator errors (i apparently can't bitshift on
> str or int?)
> 
> curious what the best way is to do this, in python...
> 
> i'll stick w/ it & post when i sort it
> 
> 
> meanwhile, any help greatly appreciated
> 
You should really use the struct module for that type of conversion, but 
you also need to know that indexing of lists and tuples starts at 0, not 1.

For the specific case that you're discussing, you could convert each 
character to its corresponding integer value and use shifting and adding 
with those:

temp = (ord(strBuf[1]) << 8) + ord(strBuf[0])

Obviously if the byte order is wrong you would need to reverse the 0 and 
1 elements.

regards
  Steve
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