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<div class="moz-cite-prefix">Dear Diego,<br>
<br>
you are right, you need to handle the case of a misprice
explicitly. If your pricer finishes without adding variables (and
your result pointer is set to SUCCESS), SCIP will assume that
there are no improving variables and use the current LP value as a
dual bound.<br>
<br>
This means, whenever you are not sure if there are more improving
variables, you should set the result pointer to DIDNOTRUN and SCIP
won't use the LP value as dual bound. On the other hand, it will
stop pricing and perform branching, which you do not want to do
either.<br>
<br>
Therefore, your pricer should just handle this case. If it
performed pricing with smoothed dual values and does not find an
improving variable, it should just perform another round of
pricing (without returning from the PRICERREDCOST callback). In
this round, you either adjust your alpha to give a higher weight
to the original dual values or just use those alone and perform
exact pricing without smoothed duals.<br>
<br>
Best,<br>
Gerald<br>
<br>
On 21.04.2015 12:50, <a class="moz-txt-link-abbreviated" href="mailto:dponce@us.es">dponce@us.es</a> wrote:<br>
</div>
<blockquote cite="mid:2ab1e2bacf7a8ccaa7b65e4546f721f3@us.es"
type="cite">
<p>Hello list,</p>
<p>as part of a Branch-and-Price procedure, I'd like to apply
stabilization in order to add less variables at the end to check
optimality. As I readed in another thread, smoothing approach
(Pessoa et al.) is a good option in SCIP.</p>
<p>I have it implemented, but it avoids correct solutions. I think
the problem is the following: when a misprice (there are columns
to add but the pricing do not provide such columns using the
convex combination) happens, the pricing detect that no
variables were added and SCIP go out the pricing before time.
How could I deal whith this problem?</p>
<p>Thanks in advance.</p>
<p>Diego.</p>
<p> </p>
<div> </div>
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