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<title>The GNU Fortran Compiler: Variable FORMAT expressions</title>

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<a name="Variable-FORMAT-expressions"></a>
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Next: <a href="Alternate-complex-function-syntax.html#Alternate-complex-function-syntax" accesskey="n" rel="next">Alternate complex function syntax</a>, Previous: <a href="ENCODE-and-DECODE-statements.html#ENCODE-and-DECODE-statements" accesskey="p" rel="prev">ENCODE and DECODE statements</a>, Up: <a href="Extensions-not-implemented-in-GNU-Fortran.html#Extensions-not-implemented-in-GNU-Fortran" accesskey="u" rel="up">Extensions not implemented in GNU Fortran</a> &nbsp; [<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="Variable-FORMAT-expressions-1"></a>
<h4 class="subsection">6.2.3 Variable <code>FORMAT</code> expressions</h4>
<a name="index-FORMAT"></a>

<p>A variable <code>FORMAT</code> expression is format statement which includes
angle brackets enclosing a Fortran expression: <code>FORMAT(I&lt;N&gt;)</code>.  GNU
Fortran does not support this legacy extension.  The effect of variable
format expressions can be reproduced by using the more powerful (and
standard) combination of internal output and string formats.  For example,
replace a code fragment like this:
</p>
<div class="smallexample">
<pre class="smallexample">      WRITE(6,20) INT1
 20   FORMAT(I&lt;N+1&gt;)
</pre></div>

<p>with the following:
</p>
<div class="smallexample">
<pre class="smallexample">c     Variable declaration
      CHARACTER(LEN=20) FMT
c     
c     Other code here...
c
      WRITE(FMT,'(&quot;(I&quot;, I0, &quot;)&quot;)') N+1
      WRITE(6,FMT) INT1
</pre></div>

<p>or with:
</p>
<div class="smallexample">
<pre class="smallexample">c     Variable declaration
      CHARACTER(LEN=20) FMT
c     
c     Other code here...
c
      WRITE(FMT,*) N+1
      WRITE(6,&quot;(I&quot; // ADJUSTL(FMT) // &quot;)&quot;) INT1
</pre></div>


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