rand() uses a random number generator from your platform. This function typically returns an integer in the range 0 to some maximum RAND_MAX. That is, the output consists of a fixed number of bits. Regardless whether you are using a pseude random number generator (which will have some kind of periodicity), or some true random source. You get 15, 16, 31, 32, 48 or some other number of bits.

All Perl is doing is do some scaling, dividing the number it got from the system by the maximum the system can return, and then multiplying it by the argument you gave to rand. Hence, the argument you give to rand has little influence on the "randomness" (there might be some roundoff errors, but they should not have much influence).

If your program repeatedly generates output, I guess your systems C library is broken. Try translating the program to an equivalent C program and see what happens.

Abigail

In reply to Re: is rand() random by Abigail-II
in thread is rand() random by thunders

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • 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:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, 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, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.