On Dec 20, 2006, at 11:02 PM, Morton Goldberg wrote:

> On Dec 20, 2006, at 4:10 PM, James Edward Gray II wrote:
>
>> On Dec 18, 2006, at 7:11 AM, Morton Goldberg wrote:
>>
>>> Here is what it produces when given 519 as its argument:
>>>
>>> Initial position 519
>>> rnbqkbnr
>>> pppppppp
>>> ........
>>> ........
>>> ........
>>> ........
>>> PPPPPPPP
>>> RNBQKBNR
>>
>> But isn't the standard position 518?
>>
>> http://en.wikipedia.org/wiki/Chess960_Enumbering_Scheme
>
>> On Dec 18, 2006, at 7:11 AM, Morton Goldberg wrote:
>>
>>>       q, @bishop_index = (number - 1).divmod 16
>>
>> I'm not sure why you subtract one here, but removing that seems to  
>> put your solution inline with output of the others.
>
> The answer to both questions is: I'm just being perverse. I decided  
> to a use one-based numbering scheme, not a zero-based one, so the  
> initial positions come out numbered 1 - 960.

Just FYI, a one-base numbering scheme is described on Wikipedia, but  
it differs from you system.

James Edward Gray II