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<h3 class="section">8.195 <code>PRODUCT</code> &mdash; Product of array elements</h3>
<p><a name="index-PRODUCT-940"></a><a name="index-array_002c-product-941"></a><a name="index-array_002c-multiply-elements-942"></a><a name="index-array_002c-conditionally-multiply-elements-943"></a><a name="index-multiply-array-elements-944"></a>
<dl>
<dt><em>Description</em>:<dd>Multiplies the elements of <var>ARRAY</var> along dimension <var>DIM</var> if
the corresponding element in <var>MASK</var> is <code>TRUE</code>.
<br><dt><em>Standard</em>:<dd>Fortran 95 and later
<br><dt><em>Class</em>:<dd>Transformational function
<br><dt><em>Syntax</em>:<dd>
<p><table summary=""><tr align="left"><td valign="top" width="80%"><code>RESULT = PRODUCT(ARRAY[, MASK])</code>
<br></td></tr><tr align="left"><td valign="top" width="80%"><code>RESULT = PRODUCT(ARRAY, DIM[, MASK])</code>
<br></td></tr></table>
<br><dt><em>Arguments</em>:<dd>
<p><table summary=""><tr align="left"><td valign="top" width="15%"><var>ARRAY</var> </td><td valign="top" width="70%">Shall be an array of type <code>INTEGER</code>,
<code>REAL</code> or <code>COMPLEX</code>.
<br></td></tr><tr align="left"><td valign="top" width="15%"><var>DIM</var> </td><td valign="top" width="70%">(Optional) shall be a scalar of type
<code>INTEGER</code> with a value in the range from 1 to n, where n
equals the rank of <var>ARRAY</var>.
<br></td></tr><tr align="left"><td valign="top" width="15%"><var>MASK</var> </td><td valign="top" width="70%">(Optional) shall be of type <code>LOGICAL</code>
and either be a scalar or an array of the same shape as <var>ARRAY</var>.
<br></td></tr></table>
<br><dt><em>Return value</em>:<dd>The result is of the same type as <var>ARRAY</var>.
<p>If <var>DIM</var> is absent, a scalar with the product of all elements in
<var>ARRAY</var> is returned. Otherwise, an array of rank n-1, where n equals
the rank of <var>ARRAY</var>, and a shape similar to that of <var>ARRAY</var> with
dimension <var>DIM</var> dropped is returned.
<br><dt><em>Example</em>:<dd>
<pre class="smallexample"> PROGRAM test_product
INTEGER :: x(5) = (/ 1, 2, 3, 4 ,5 /)
print *, PRODUCT(x) ! all elements, product = 120
print *, PRODUCT(x, MASK=MOD(x, 2)==1) ! odd elements, product = 15
END PROGRAM
</pre>
<br><dt><em>See also</em>:<dd><a href="SUM.html#SUM">SUM</a>
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