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    <div class="moz-cite-prefix">Hi Samuel and list,<br>
      <br>
      Am 18.02.2016 um 14:02 schrieb Deleplanque Samuel:<br>
    </div>
    <blockquote
cite="mid:CAAO5AhBJYE2g7kiK4hVj0F+eR9Gp1gJJbXU8xexs1uUsDzde6g@mail.gmail.com"
      type="cite">
      <div dir="ltr">Dear SCIP team,
        <div><br>
        </div>
        <div>I'm working on a typical pricing problem. I've two
          formulations: one is solved with a Branch & Price and the
          other one with a typical Branch & Bound, both using SCIP.</div>
        <div>I have a problem with collecting the LP Root for the second
          one. Indeed, I would like the LP-Relaxation objective value of
          my problem and not the transformed one, or any other solution
          obtained in the root node.</div>
      </div>
    </blockquote>
    You should use SCIPretransformObjval(scip, transformedobjval) to
    transform objective values from the transformed space back to the
    original problem space. By convention, we call values in the
    transformed space the lower and upper bound and their original
    counterparts dual and primal bound, respectively.<br>
    <br>
    In order to obtain the first LP value, you can use the special
    function SCIPgetFirstLPDualboundRoot(scip).<br>
    <br>
    <blockquote
cite="mid:CAAO5AhBJYE2g7kiK4hVj0F+eR9Gp1gJJbXU8xexs1uUsDzde6g@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div><br>
        </div>
        <div>For example, in the trace bellow, the LP-Relaxation
          objective value for an instance of my formulation is
          1.041834e+04 (the MIP optimal is found before any branching).</div>
        <div><br>
        </div>
        <div> time | node  | left  |LP iter|LP it/n| mem |mdpt |frac
          |vars |cons |cols |rows |cuts |confs|strbr|  dualbound   |
          primalbound  |  gap   <br>
        </div>
        <div>
          <div>T 0.0s|     1 |     0 |     0 |     - | 248k|   0 |   - |
             10 |  20 |  10 |  20 |   0 |   0 |   0 |      --      |
            0.000000e+00 |    Inf </div>
          <div>  0.0s|     1 |     0 |    13 |     - | 246k|   0 |   2 |
             10 |  20 |  10 |  20 |   0 |   0 |   0 | 1.041834e+04 |
            0.000000e+00 |    Inf </div>
          <div>s 0.0s|     1 |     0 |    13 |     - | 247k|   0 |   2 |
             10 |  20 |  10 |  20 |   0 |   0 |   0 | 1.041834e+04 |
            3.029395e+03 | 243.91%</div>
          <div>  0.0s|     1 |     0 |    16 |     - | 248k|   0 |   0 |
             10 |  20 |  10 |  21 |   1 |   0 |   0 | 9.957000e+03 |
            3.029395e+03 | 228.68%</div>
          <div>* 0.0s|     1 |     0 |    16 |     - | 248k|   0 |   - |
             10 |  20 |  10 |  21 |   1 |   0 |   0 | 9.957000e+03 |
            9.957000e+03 |   0.00%</div>
        </div>
        <div><br>
        </div>
        <div>If I use any function to obtain the LPRoot value (<i>SCIPgetLPRootObjval</i>,
          <i>SCIPgetLPRootObjval</i> or <i>SCIPgetLowerboundRoot</i>) I
          logically get 9.957000e+03. If I use <i>SCIPgetSolOrigObj</i>
          I obtain the same and not the 1.041834e+04 of the LP
          relaxation of my original problem.</div>
        <div><br>
        </div>
        <div>Also, because I want to compare the two formulations, and
          then to compare what is comparable, I would like to know what
          are the different algorithms executed in the root. If I try to
          understand: the T and s mean two heuristics has been used and
          * means normally an integral LP-relaxation (but not for my
          original problem).</div>
      </div>
    </blockquote>
    Exactly. Use 'display statistics' or SCIPprintStatistics() to print
    an exhaustive plugin summary to see which of the plugins ran, which
    succeeded, and which wasted your precious user time. All these
    statistics are also available through the API, but I would suggest
    to have a look at the tabular output first to get an impression of
    what is important.<br>
    <br>
    A list of the primal heuristics of SCIP and their display characters
    is available with the command 'display heuristics'.<br>
    <br>
    Kind regards,<br>
    Gregor<br>
    <br>
    <blockquote
cite="mid:CAAO5AhBJYE2g7kiK4hVj0F+eR9Gp1gJJbXU8xexs1uUsDzde6g@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div><br>
        </div>
        <div>Thanks :)</div>
        <div><br>
        </div>
        <div>Samuel Deleplanque</div>
        <div><br>
        </div>
        <div>-- <br>
          <div class="gmail_signature">
            <div dir="ltr">
              <div style="font-family:arial"><span
                  style="color:rgb(68,68,68);font-family:'courier
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              </div>
              <div style="font-family:arial"><font size="1"><span
                    style="color:rgb(68,68,68);font-family:'courier
                    new',monospace">Samuel Deleplanque, PHD</span><span
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                      color="#000000"><b><br>
                      </b></font></span></font></div>
              <div style="font-family:arial"><span
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                    color="#000000" size="1"><b>PostDoc at <i>Université
                        Libre de Bruxelles</i></b></font></span></div>
              <div style="font-family:arial"><font size="1"><b
style="font-family:OpenSans,Tahoma,Arial,Verdana;line-height:17px;text-align:justify">Phone:</b><span
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style="font-family:OpenSans,Tahoma,Arial,Verdana;line-height:17px;text-align:justify"><b>Office:</b> 2.N3.206
                    - Building NO, <span
                      style="color:rgb(0,0,0);font-family:arial;line-height:normal">Campus
                      de la Plaine</span></span></font></div>
              <div style="font-family:arial"><font color="#000000"
                  size="1">Boulevard du Triomphe CP 210 / 01<br>
                </font></div>
              <font size="1"><font style="font-family:arial"
                  color="#000000">B-1050 <b>Brussels</b>, <b>Belgium    
                                          </b></font><b
                  style="font-family:arial;color:rgb(0,0,0)"><i><a
                      moz-do-not-send="true"
                      href="http://sites.google.com/site/samueldeleplanque/"
                      target="_blank">Website</a></i></b></font>
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      <pre wrap="">_______________________________________________
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    </blockquote>
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