Re: Simple disk-based sorting method

On Sat, 14 Apr 2007 17:04:37 -0400, Bob Stearns
<rstearns1241@[EMAIL PROTECTED]
> wrote:

>> Now I want to sort another data set but this time the key consists of
>> a 4 digit number that can be either plus or minus and I want a
>> descending sort order.
 
>How about just using the whole number + 10000 to select the random 
>location in the disk dataset then reading the disk dataset sequentially, 
>ignoring any empty locations? If that won't work, then you don't have 
>unique keys.

I think I may do something similar to that. I create the data set in
another part of the application so I can discover the max and min
values for the key. I can use the min value to offset all the keys to
a positive value and then sort on that pseudo-key. After sorting I can
subtract the offset back out and recover the original keys. I would
use the max value to set the fixed length of the key. By padding the
key with a format like "%05d" (zero fill left side to give a total of
5 digits), the sorting procedure is easier since there is always a
digit in every position.


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