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Both the timing routines and the test routines call SECOND
(DSECND), a real function with no arguments that returns the time
in seconds from some fixed starting time.
Our version of this routine returns only ``user time'', and
not ``user time 10#10 system time''.
The version of second in SECONDF calls ETIME, a Fortran library
routine available on some computer systems.
If ETIME is not available or a better local timing function exists,
you will have to provide the correct interface to SECOND and DSECND
on your machine.
The test program in TSECONDF
performs a million operations using 5000 iterations of
the SAXPY operation
11#11 on a vector of length 100.
The total time and megaflops for this test is reported, then
the operation is repeated including a call to SECOND on each of
the 5000 iterations to determine the overhead due to calling SECOND.
Compile SECONDF and TSECONDF and run the test program.
There is no single right answer, but the times
in seconds should be positive and the megaflop ratios should be
appropriate for your machine.
Repeat this test for DSECNDF and TDSECNDF and
save SECOND and DSECND for inclusion in the LAPACK library in
Section A.5.

** Next:** Testing IEEE arithmetic and
** Up:** Test and Install the
** Previous:** Installing SLAMCH and DLAMCH
** Contents**
Susan Blackford
2001-08-13