[Tutor] working with bit arrays

[Dave Angel]

Robert Berman wrote:
> Emille,
>
> I do think he meant bit 20 to 32 rather than 20 to 40. Unless, of
> course, he's dealing with a 64 bit word.
>
>   
You posted out of order (top--osted).  So I am forced to put my response 
elsewhere.
> I am delighted with all the help I have received on this topic and I am
> gleefully learning anding and oring, but not too much on the EOR side.
>
> Thanks again for all the assistance.
>
> Robert
>
> On Wed, 2009-12-02 at 17:17 -0800, Emile van Sebille wrote:
>
>   
>> On 12/2/2009 4:10 PM GilJohnson said...
>> <snip>
>>     
>>> Using an array of 32 bit integers, you have to go to some
>>> trouble to slice out, say, bits 20 to 40.
>>>       
>> I think I agree -- if in fact it's not impossible.  Tell me that's a 
>> typo or take a moment to explain what I'm misunderstanding...
>>
>> Emile
>>
>>
>>     
Once you have an *array* of integers, you have much more than 32 bits to 
work with.  For example, with an array of size 10, you now have 320 bits 
to work with.  He's just pointing out that it's a little bit awkward to 
address a group of bits that are not all in the same int.  So bits 5-20 
would be easy, while bits 29-40 would be much harder.

DaveA