<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Just an ignorant assumption, but would not the output of [noise~] itself be generated from pseudo-random numbers? If not, then how does [noise~] generate its randomness? Or is there something more complex at work?<div><br></div><div>Ian</div><div><br><div><div>On 05/07/2009, at 7:12 PM, Andrew Faraday wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Verdana; font-size: 13px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><br class="Apple-interchange-newline">Just an idea, but if the hardware random number generators use a jittery oscillator etc. Why not use [noise~] and [snapshot~] followed by some arithmetic and [int] you could build what I assume would be more random than the [random] box.<div><br></div><div>Andrew</div><div><br>> Date: Sun, 5 Jul 2009 00:22:51 -0400<br>> From:<span class="Apple-converted-space"> </span><a href="mailto:martin.peach@sympatico.ca">martin.peach@sympatico.ca</a><br>> To:<span class="Apple-converted-space"> </span><a href="mailto:mmoserbooth@gmail.com">mmoserbooth@gmail.com</a><br>> CC:<span class="Apple-converted-space"> </span><a href="mailto:pd-list@iem.at">pd-list@iem.at</a>;<span class="Apple-converted-space"> </span><a href="mailto:zmoelnig@iem.at">zmoelnig@iem.at</a><br>> Subject: Re: [PD] help_random/seed<br>><span class="Apple-converted-space"> </span><br>> Mike Moser-Booth wrote:<br>> > IOhannes m zmölnig wrote:<br>> >> Frank Barknecht wrote:<br>> >>> Hallo,<br>> >>> cem guney hat gesagt: // cem guney wrote:<br>> >>><br>> >>>> just started studying PD. going through the control examples i've<span class="Apple-converted-space"> </span><br>> >>>> been stuck trying to figure out the function of the message, seed<span class="Apple-converted-space"> </span><br>> >>>> 123 in the<br>> >>>> example for "random". not sure if i figured out the explanation below,<br>> >>>><br>> >>>> Seeds are kept locally so that if two Randoms are seeded the same<span class="Apple-converted-space"> </span><br>> >>>> they will have the same output (or indeed you can seed the same one<span class="Apple-converted-space"> </span><br>> >>>> twice to repeat the output.)<br>> >>><br>> >>> Yes, that's true, you understood correctly.<br>> >>><br>> >>> Oh, wait, that's what's in the help-file! What exactly is cloudy there?<br>> >><br>> >> probably the simple fact, that [random] despite of it's name does not<span class="Apple-converted-space"> </span><br>> >> really produce random numbers.<br>> >> mostly when computers present you a "random" number, then this number<span class="Apple-converted-space"> </span><br>> >> will only appear to be random, but in reality is just calculated as<span class="Apple-converted-space"> </span><br>> >> the next item of a totally deterministic series.<br>> >> (as a matter of fact, a new random number is usually generated by<span class="Apple-converted-space"> </span><br>> >> simple taking the last number and then applying some more or less<span class="Apple-converted-space"> </span><br>> >> complicated transformation on this number). this method is known as<span class="Apple-converted-space"> </span><br>> >> "pseudo random".<br>> >><br>> >> you can set the "starting point" of the series by setting the "seed",<span class="Apple-converted-space"> </span><br>> >> which is the first number of the random sequence). since all [random]<span class="Apple-converted-space"> </span><br>> >> object use the same algorithm to calculate the next pseudo-random<span class="Apple-converted-space"> </span><br>> >> number, they will all end up with the same sequence if they all start<span class="Apple-converted-space"> </span><br>> >> with the same "seed".<br>> >> by default Pd uses different seeds for all [random] objects so they<span class="Apple-converted-space"> </span><br>> >> all appear to work independently.<br>> > In addition, it's probably worth mentioning that Pd will produce the<span class="Apple-converted-space"> </span><br>> > same seeds for each [random] every time you load the patch. So while<span class="Apple-converted-space"> </span><br>> > they appear to work independently, you will still get the same results<span class="Apple-converted-space"> </span><br>> > each time you first run a patch after loading it.<br>> ><span class="Apple-converted-space"> </span><br>><span class="Apple-converted-space"> </span><br>> A lot of the latest cpus have hardware random number generators that<span class="Apple-converted-space"> </span><br>> work by having a jittery oscillator sample the cpu clock, or something<span class="Apple-converted-space"> </span><br>> along those lines. (Such a jittery oscillator is assumed to have<span class="Apple-converted-space"> </span><br>> normally distributed transition times.)<br>> It would be nice if the random source could be independently specified<span class="Apple-converted-space"> </span><br>> for all the pd objects that use random numbers, since the count of<span class="Apple-converted-space"> </span><br>> unreachable combinations when using the standard deterministic chaos<span class="Apple-converted-space"> </span><br>> generators is infinite.<br>><span class="Apple-converted-space"> </span><br>> Martin<br>><span class="Apple-converted-space"> </span><br>><span class="Apple-converted-space"> </span><br>> _______________________________________________<br>><span class="Apple-converted-space"> </span><a href="mailto:Pd-list@iem.at">Pd-list@iem.at</a><span class="Apple-converted-space"> </span>mailing list<br>> UNSUBSCRIBE and account-management -><span class="Apple-converted-space"> </span><a href="http://lists.puredata.info/listinfo/pd-list">http://lists.puredata.info/listinfo/pd-list</a><br></div><br><hr>Upgrade to Internet Explorer 8 Optimised for MSN.<span class="Apple-converted-space"> </span><a href="http://extras.uk.msn.com/internet-explorer-8/?ocid=T010MSN07A0716U" target="_new">Download Now</a><span class="Apple-converted-space"> </span>_______________________________________________<br><a href="mailto:Pd-list@iem.at">Pd-list@iem.at</a><span class="Apple-converted-space"> </span>mailing list<br>UNSUBSCRIBE and account-management -><span class="Apple-converted-space"> </span><a href="http://lists.puredata.info/listinfo/pd-list">http://lists.puredata.info/listinfo/pd-list</a><br></span></blockquote></div><br></div></body></html>