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<title>The GNU Fortran Compiler: Old-style variable initialization</title>
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Next: <a href="Extensions-to-namelist.html#Extensions-to-namelist" accesskey="n" rel="next">Extensions to namelist</a>, Previous: <a href="Old_002dstyle-kind-specifications.html#Old_002dstyle-kind-specifications" accesskey="p" rel="prev">Old-style kind specifications</a>, Up: <a href="Extensions-implemented-in-GNU-Fortran.html#Extensions-implemented-in-GNU-Fortran" accesskey="u" rel="up">Extensions implemented in GNU Fortran</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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<a name="Old_002dstyle-variable-initialization-1"></a>
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<h4 class="subsection">6.1.2 Old-style variable initialization</h4>
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<p>GNU Fortran allows old-style initialization of variables of the
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form:
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</p><div class="smallexample">
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<pre class="smallexample"> INTEGER i/1/,j/2/
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REAL x(2,2) /3*0.,1./
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</pre></div>
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<p>The syntax for the initializers is as for the <code>DATA</code> statement, but
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unlike in a <code>DATA</code> statement, an initializer only applies to the
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variable immediately preceding the initialization. In other words,
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something like <code>INTEGER I,J/2,3/</code> is not valid. This style of
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initialization is only allowed in declarations without double colons
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(<code>::</code>); the double colons were introduced in Fortran 90, which also
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introduced a standard syntax for initializing variables in type
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declarations.
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</p>
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<p>Examples of standard-conforming code equivalent to the above example
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are:
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</p><div class="smallexample">
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<pre class="smallexample">! Fortran 90
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INTEGER :: i = 1, j = 2
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REAL :: x(2,2) = RESHAPE((/0.,0.,0.,1./),SHAPE(x))
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! Fortran 77
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INTEGER i, j
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REAL x(2,2)
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DATA i/1/, j/2/, x/3*0.,1./
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</pre></div>
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<p>Note that variables which are explicitly initialized in declarations
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or in <code>DATA</code> statements automatically acquire the <code>SAVE</code>
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attribute.
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