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<title>The GNU Fortran Compiler: ENCODE and DECODE statements</title>
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<a name="ENCODE-and-DECODE-statements"></a>
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<p>
Next: <a href="Variable-FORMAT-expressions.html#Variable-FORMAT-expressions" accesskey="n" rel="next">Variable FORMAT expressions</a>, Previous: <a href="STRUCTURE-and-RECORD.html#STRUCTURE-and-RECORD" accesskey="p" rel="prev">STRUCTURE and RECORD</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="ENCODE-and-DECODE-statements-1"></a>
<h4 class="subsection">6.2.2 <code>ENCODE</code> and <code>DECODE</code> statements</h4>
<a name="index-ENCODE"></a>
<a name="index-DECODE"></a>
<p>GNU Fortran does not support the <code>ENCODE</code> and <code>DECODE</code>
statements. These statements are best replaced by <code>READ</code> and
<code>WRITE</code> statements involving internal files (<code>CHARACTER</code>
variables and arrays), which have been part of the Fortran standard since
Fortran 77. For example, replace a code fragment like
</p>
<div class="smallexample">
<pre class="smallexample"> INTEGER*1 LINE(80)
REAL A, B, C
c ... Code that sets LINE
DECODE (80, 9000, LINE) A, B, C
9000 FORMAT (1X, 3(F10.5))
</pre></div>
<p>with the following:
</p>
<div class="smallexample">
<pre class="smallexample"> CHARACTER(LEN=80) LINE
REAL A, B, C
c ... Code that sets LINE
READ (UNIT=LINE, FMT=9000) A, B, C
9000 FORMAT (1X, 3(F10.5))
</pre></div>
<p>Similarly, replace a code fragment like
</p>
<div class="smallexample">
<pre class="smallexample"> INTEGER*1 LINE(80)
REAL A, B, C
c ... Code that sets A, B and C
ENCODE (80, 9000, LINE) A, B, C
9000 FORMAT (1X, 'OUTPUT IS ', 3(F10.5))
</pre></div>
<p>with the following:
</p>
<div class="smallexample">
<pre class="smallexample"> CHARACTER(LEN=80) LINE
REAL A, B, C
c ... Code that sets A, B and C
WRITE (UNIT=LINE, FMT=9000) A, B, C
9000 FORMAT (1X, 'OUTPUT IS ', 3(F10.5))
</pre></div>
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