As anon monk already said, turn on warnings. He is wrong on the cause of your problem though, $tsize[$tnum] is (as you expected) the size of the array in the hash of arrays

But in the following line you write $thread[$i] which would try to access an element of the array @thread which simply doesn't exist. What you wanted to do was: 
    for ($i=0; $i<$tsize[$tnum] ; $i++) 
    { $tlist[$tnum][$i] = $threads{$thread}[$i];

[download]

Note that you can eliminate this loop. The following is equivalent to the two lines above

    push( @{$tlist[$tnum]},  @{$threads{$thread}} );

[download]

In reply to Re: syntax of multidimensional arrays and hashes by jethro
in thread syntax of multidimensional arrays and hashes by hsfrey

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.