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<title>The GNU Fortran Compiler: SRAND</title>
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<a name="SRAND"></a>
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<p>
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Next: <a href="STAT.html#STAT" accesskey="n" rel="next">STAT</a>, Previous: <a href="SQRT.html#SQRT" accesskey="p" rel="prev">SQRT</a>, Up: <a href="Intrinsic-Procedures.html#Intrinsic-Procedures" accesskey="u" rel="up">Intrinsic Procedures</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
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<a name="SRAND-_002d_002d_002d-Reinitialize-the-random-number-generator"></a>
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<h3 class="section">9.248 <code>SRAND</code> — Reinitialize the random number generator</h3>
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<a name="index-SRAND"></a>
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<a name="index-random-number-generation_002c-seeding-1"></a>
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<a name="index-seeding-a-random-number-generator-1"></a>
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<dl compact="compact">
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<dt><em>Description</em>:</dt>
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<dd><p><code>SRAND</code> reinitializes the pseudo-random number generator
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called by <code>RAND</code> and <code>IRAND</code>. The new seed used by the
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generator is specified by the required argument <var>SEED</var>.
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</p>
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</dd>
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<dt><em>Standard</em>:</dt>
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<dd><p>GNU extension
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</p>
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</dd>
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<dt><em>Class</em>:</dt>
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<dd><p>Subroutine
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</p>
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</dd>
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<dt><em>Syntax</em>:</dt>
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<dd><p><code>CALL SRAND(SEED)</code>
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</p>
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</dd>
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<dt><em>Arguments</em>:</dt>
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<dd><table>
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<tr><td width="15%"><var>SEED</var></td><td width="70%">Shall be a scalar <code>INTEGER(kind=4)</code>.</td></tr>
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</table>
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</dd>
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<dt><em>Return value</em>:</dt>
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<dd><p>Does not return anything.
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</p>
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</dd>
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<dt><em>Example</em>:</dt>
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<dd><p>See <code>RAND</code> and <code>IRAND</code> for examples.
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</p>
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</dd>
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<dt><em>Notes</em>:</dt>
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<dd><p>The Fortran standard specifies the intrinsic subroutines
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<code>RANDOM_SEED</code> to initialize the pseudo-random number
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generator and <code>RANDOM_NUMBER</code> to generate pseudo-random numbers.
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These subroutines should be used in new codes.
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</p>
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<p>Please note that in GNU Fortran, these two sets of intrinsics (<code>RAND</code>,
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<code>IRAND</code> and <code>SRAND</code> on the one hand, <code>RANDOM_NUMBER</code> and
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<code>RANDOM_SEED</code> on the other hand) access two independent
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pseudo-random number generators.
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</p>
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</dd>
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<dt><em>See also</em>:</dt>
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<dd><p><a href="RAND.html#RAND">RAND</a>, <a href="RANDOM_005fSEED.html#RANDOM_005fSEED">RANDOM_SEED</a>, <a href="RANDOM_005fNUMBER.html#RANDOM_005fNUMBER">RANDOM_NUMBER</a>
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