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ETIME
— Execution time subroutine (or function)ETIME(VALUES, TIME)
returns the number of seconds of runtime
since the start of the process's execution in TIME. VALUES
returns the user and system components of this time in VALUES(1)
and
VALUES(2)
respectively. TIME is equal to VALUES(1) + VALUES(2)
.
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.
This intrinsic is provided in both subroutine and function forms; however, only one form can be used in any given program unit.
VALUES and TIME are INTENT(OUT)
and provide the following:
VALUES(1) : | User time in seconds.
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VALUES(2) : | System time in seconds.
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TIME : | Run time since start in seconds.
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CALL ETIME(VALUES, TIME) .
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TIME = ETIME(VALUES) , (not recommended).
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VALUES | The type shall be REAL(4), DIMENSION(2) .
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TIME | The type shall be REAL(4) .
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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