Another possibility would be to keep, for each IP address, a shuffled list of numbers [1..n] if you see that you do not have one already for this IP. Subsequent actual “shuffles” of the data would use the elements in this pre-shuffled list. (Another way to say it is to capture the successive results from rand($i+1) as per the algorithm code-sample above, and re-use them.) This has the possible advantage that it does not tamper with the (after all, global...) random-number seed value. (Fiddling with the seed, of course, has a potential negative effect on other intended-to-be random sequences that your program might need to generate for other, unrelated purposes. Capturing and re-using a sequence avoids this. There might be another way to do it of which I am simply not aware.)
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.
| & || & |
| < || < |
| > || > |
| [ || [ |
| ] || ] ||