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<h3 class="section">8.74 <code>ETIME</code> — Execution time subroutine (or function)</h3>
<p><a name="index-ETIME-579"></a><a name="index-time_002c-elapsed-580"></a>
<dl>
<dt><em>Description</em>:<dd><code>ETIME(VALUES, TIME)</code> returns the number of seconds of runtime
since the start of the process's execution in <var>TIME</var>. <var>VALUES</var>
returns the user and system components of this time in <code>VALUES(1)</code> and
<code>VALUES(2)</code> respectively. <var>TIME</var> is equal to <code>VALUES(1) + VALUES(2)</code>.
<p>On some systems, the underlying timings are represented using types with
sufficiently small limits that overflows (wrap around) are possible, such as
32-bit types. Therefore, the values returned by this intrinsic might be, or
become, negative, or numerically less than previous values, during a single
run of the compiled program.
<p>This intrinsic is provided in both subroutine and function forms; however,
only one form can be used in any given program unit.
<p><var>VALUES</var> and <var>TIME</var> are <code>INTENT(OUT)</code> and provide the following:
<p><table summary=""><tr align="left"><td valign="top" width="15%"></td><td valign="top" width="30%"><code>VALUES(1)</code>: </td><td valign="top" width="60%">User time in seconds.
<br></td></tr><tr align="left"><td valign="top" width="15%"></td><td valign="top" width="30%"><code>VALUES(2)</code>: </td><td valign="top" width="60%">System time in seconds.
<br></td></tr><tr align="left"><td valign="top" width="15%"></td><td valign="top" width="30%"><code>TIME</code>: </td><td valign="top" width="60%">Run time since start in seconds.
<br></td></tr></table>
<br><dt><em>Standard</em>:<dd>GNU extension
<br><dt><em>Class</em>:<dd>Subroutine, function
<br><dt><em>Syntax</em>:<dd>
<p><table summary=""><tr align="left"><td valign="top" width="80%"><code>CALL ETIME(VALUES, TIME)</code>.
<br></td></tr><tr align="left"><td valign="top" width="80%"><code>TIME = ETIME(VALUES)</code>, (not recommended).
<br></td></tr></table>
<br><dt><em>Arguments</em>:<dd>
<p><table summary=""><tr align="left"><td valign="top" width="15%"><var>VALUES</var></td><td valign="top" width="70%">The type shall be <code>REAL(4), DIMENSION(2)</code>.
<br></td></tr><tr align="left"><td valign="top" width="15%"><var>TIME</var></td><td valign="top" width="70%">The type shall be <code>REAL(4)</code>.
<br></td></tr></table>
<br><dt><em>Return value</em>:<dd>Elapsed time in seconds since the start of program execution.
<br><dt><em>Example</em>:<dd>
<pre class="smallexample"> program test_etime
integer(8) :: i, j
real, dimension(2) :: tarray
real :: result
call ETIME(tarray, result)
print *, result
print *, tarray(1)
print *, tarray(2)
do i=1,100000000 ! Just a delay
j = i * i - i
end do
call ETIME(tarray, result)
print *, result
print *, tarray(1)
print *, tarray(2)
end program test_etime
</pre>
<br><dt><em>See also</em>:<dd><a href="CPU_005fTIME.html#CPU_005fTIME">CPU_TIME</a>
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