3 <title>Random-Number Seed</title>
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9 <h2>Random-Number Seed</h2>
11 The seed of the random number generator can be set as follows:
13 <p/><code>flag </code><strong> Random:setSeed </strong>
14 (<code>default = <strong>off</strong></code>)<br/>
15 Indicates whether a user-set seed should be used every time the
16 <code>Pythia::init</code> routine is called. If off, the random number
17 generator is initialized with its default seed at the beginning
18 of the run, and never again. If on, each new <code>Pythia::init</code>
19 call (should several be made in the same run) results in the random
20 number being re-initialized, thereby possibly starting over with the
21 same sequence, if you do not watch out.
24 <p/><code>mode </code><strong> Random:seed </strong>
25 (<code>default = <strong>-1</strong></code>; <code>maximum = 900000000</code>)<br/>
26 The seed to be used, if <code>setSeed</code> is on.<br/>
27 A negative value gives the default seed,<br/>
28 a value 0 gives a random seed based on the time, and<br/>
29 a value between 1 and 900,000,000 a unique different random number
34 For more on random numbers see <a href="RandomNumbers.html" target="page">here</a>.
35 This includes methods to save and restore the state of the generator,
36 and some preprogrammed methods to generate non-uniform random numbers.
41 <!-- Copyright (C) 2010 Torbjorn Sjostrand -->