include 'debug.h' ndigit = -3 logfil = 6 msgets = 0 msaitr = 0 msapps = 0 msaupd = 1 msaup2 = 0 mseigt = 0 mseupd = 0 |

ARPACK provides a means to trace the progress of the computation
as it proceeds. Various levels of output may be specified
from no output (`level = 0 `) to voluminous (`level = 3`) .
The code segment listed in Figure 2.5 gives an example
of the statements that may be used within the calling program to
initiate and request this output.

The include statement sets up the storage declarations that are
solely associated with this trace debugging feature. The
parameter `ndigit` specifies the number of decimal digits and the
width of the output lines. A positive or negative value of `ndigit`
specifies that `132` or `80` columns, respectively, are used
during output.
The parameter `logfil` specifies the logical unit number
of the output file. The values of the remaining parameters
indicate the output levels from the indicated routines. For
example, `msaitr` indicates the level of output requested
from the subroutine `dsaitr`. The above configuration will
give a breakdown of the number of matrix vector products required,
the total number of iterations, the number of re-orthogonalization
steps and an estimate of the time spent in each routine and phase of the
computation. Figure 2.6 displays the output produced by the
above settings. The user is encouraged to experiment with
the other settings once some familiarity has been gained with
the routines. See Appendix B for a detailed discussion of the Trace
Debugging Capabilities.

========================================== = Symmetric implicit Arnoldi update code = = Version Number: 2.1 = = Version Date: 11/15/95 = ========================================== = Summary of timing statistics = ========================================== Total number update iterations = 8 Total number of OP*x operations = 125 Total number of B*x operations = 0 Total number of reorthogonalization steps = 125 Total number of iterative refinement steps = 0 Total number of restart steps = 0 Total time in user OP*x operation = 0.020002 Total time in user B*x operation = 0.000000 Total time in Arnoldi update routine = 0.210021 Total time in ssaup2 routine = 0.190019 Total time in basic Arnoldi iteration loop = 0.110011 Total time in reorthogonalization phase = 0.070007 Total time in (re)start vector generation = 0.000000 Total time in trid eigenvalue subproblem = 0.040004 Total time in getting the shifts = 0.000000 Total time in applying the shifts = 0.040004 Total time in convergence testing = 0.000000 |