[Tutor] modulo

[Dave Angel]

On 10/07/2012 08:00 PM, Jan Karel Schreuder wrote:
> 
> 
> On Oct 7, 2012, at 7:24 PM, Dave Angel <d at davea.name> wrote:
> 
>>>>>
>>>>
>>
>> It still makes no sense to me.  There are at least two equally silly
>> ways to define the results of a negative modulus, and you've properly
>> described one of them, presumably the one that Python implements.
>>
>> But I've used and abused about 35 languages over the years, and each
>> makes its own choice for this.  I'd rather just call it undefined, and
>> eliminate it.  That's what we did when the hardware guys couldn't decide
>> how the hardware was going to respond to a particular microcode bit
>> pattern.  They documented it as undefined, and I made it illegal in the
>> microcode assembler.
>>
>> Fortunately, the OP isn't asking about this case, which is the other
>> reason I didn't bother to describe what Python does.
>>
>>
>>
>> -- 
>>
>> DaveA
>> _______________________________________________
>> I'm not a professional programmer, so I might be way off base here. But what I like about Pythons modulo solution is that I can use it to right and left shift in lists or tuples, and I will link to the first element when I right shift past the last element and link to the last element when I left shift past the first element. In other words I can consider the last as a chain where the last and the first element are connected. This I find useful in surprisingly many situations. 
> 
> 
Certainly, but you've never had to do that with lists or tuples having
negative lengths.  It's a negative modulus that I'm complaining about.


-- 

DaveA