The way people make letter frequency tables is by taking a large sample of text and counting the number of occurrences of each letter.

In the old days, this was tedious and time-consuming, so people used the same tables over and over.

Nowadays, we have computers to do this for us. Just acquire a large sample of text and write a Perl program to count symbol frequencies. The Perl program will be about ten lines long. Then you can make sure that the sample text is similar the sorts of messages you are planning to decode, and you can arrange for the table to include exactly the items that you want it to.

You can do even better by having it count trigraph frequencies (that's the frequency of a particular sequence of three characters, like har) and plugging that table into your brute-forcer instead.

In reply to Re: Letter frequencies by Dominus
in thread Letter frequencies by Leitchn

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.