Beefy Boxes and Bandwidth Generously Provided by pair Networks
Think about Loose Coupling

comment on

( #3333=superdoc: print w/replies, xml ) Need Help??
There's predictability and there's predictibility. It tends to be bad for simulations if your "random" numbers start being the same on every pass through the main loop.
It all depends on the application. Perhaps you are looking for something in a large set with a certain property. So, rather than iterate through, you pick a random starting point. IIRC, there are non-deterministic primality tests that take a random input and tell you whether a number is composite or not. In this case, you want to keep the one random input that tells you that the number under examination is composite if you want to prove it. If I can find an example of such an algorithm later, I'll update this node.
Entropy measures the number of possible states of a system. Determinism is about the transitions between states. The two concepts are largely orthogonal.
Yes. However, this does not contradict anything that I said. Some people were concerned about repeated calls to rand() reducing the strength of randomness of data received from places like /dev/rand and such. I was saying that this was not the case, as perl uses a PRNG, which given a specific input is completely deterministic.


Update: Check this out.

In reply to Re: Re: Re: Can I seed srand() with results from rand()? by thor
in thread Can I seed srand() with results from rand()? by blokhead

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

  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?

What's my password?
Create A New User
Domain Nodelet?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others examining the Monastery: (2)
As of 2023-02-03 01:05 GMT
Find Nodes?
    Voting Booth?
    I prefer not to run the latest version of Perl because:

    Results (24 votes). Check out past polls.