Decision Optimization

Decision Optimization

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  • 1.  Interpreting barrier log file

    Posted 07/12/10 02:43 PM

    Originally posted by: vdesai


    Hi all,
    I am having difficulty in understanding something from barrier log file.

    1) I sometimes get messages of the type:
    Refinement - orig 2.45e-07, refined 2.45e-07, target 4.00e-06, 0 iter

    From my experience the solution does not seem right when I get too many of these messages.
    Below is a small excerpt from the log file.
    Tried aggregator 1 time.
    LP Presolve eliminated 4000 rows and 26 columns.
    Reduced LP has 4054 rows, 32963 columns, and 1004963 nonzeros.
    Presolve time = 0.67 sec.
    Parallel mode: using up to 8 threads for barrier.
    Looking for dense columns with more than 56 nonzeros.
    Number of nonzeros in lower triangle of A*A' = 217431
    Using Approximate Minimum Degree ordering
    Total time for automatic ordering = 0.12 sec.
    Summary statistics for Cholesky factor:
    Threads = 8
    Rows in Factor = 4054
    Integer space required = 217786
    Total non-zeros in factor = 222346
    Total FP ops to factor = 12272486
    L has 3959 super-nodes.
    Histogram of super-node widths:
    SupWidth: 1 96
    Number: 3958 1

    0.26s for iteration (0.21s, 253 Mflops for lin. solve)
    Max number of central corrections is 0
    Itn Primal Obj Dual Obj Prim Inf Upper Inf Dual Inf
    0 1.8379841e+06 0.0000000e+00 3.56e+05 0.00e+00 3.92e+05
    0.23s for iteration (0.20s, 258 Mflops for lin. solve)
    1 1.7470795e+06 1.0507424e+04 3.43e+05 0.00e+00 3.42e+05
    0.27s for iteration (0.20s, 268 Mflops for lin. solve)
    2 1.3886718e+06 6.7192699e+04 2.76e+05 0.00e+00 3.62e-07
    0.25s for iteration (0.20s, 259 Mflops for lin. solve)
    3 2.2744777e+04 6.5930201e+04 3.37e-07 0.00e+00 3.80e-07
    0.29s for iteration (0.22s, 238 Mflops for lin. solve)
    Refinement - orig 2.45e-07, refined 2.45e-07, target 4.00e-06, 0 iter
    4 2.6365237e+04 4.0174035e+04 2.20e-07 0.00e+00 2.83e-07
    0.28s for iteration (0.20s, 259 Mflops for lin. solve)
    Refinement - orig 2.33e-06, refined 2.33e-06, target 4.00e-06, 0 iter
    5 2.8368577e+04 3.5427188e+04 8.82e-07 0.00e+00 1.86e-07
    0.26s for iteration (0.21s, 253 Mflops for lin. solve)
    Refinement - orig 7.33e-07, refined 7.33e-07, target 4.00e-06, 0 iter
    6 3.0285482e+04 3.4574844e+04 6.70e-07 0.00e+00 1.23e-07
    0.27s for iteration (0.22s, 237 Mflops for lin. solve)

    Can some
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  • 2.  Re: Interpreting barrier log file

    Posted 07/12/10 02:47 PM

    Originally posted by: vdesai


    Sorry, this got posted while I was still working on it. I will post the final one again.
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