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<h1>set_bb_depthlimit</h1>
<p>
Sets the maximum branch-and-bound depth.</p>
<p><b>void set_bb_depthlimit(lprec </b>*<i>lp</i><b>, int </b><i>bb_maxlevel</i><b>);</b></p>
<p class="label"><b>Return Value</b></p>
<p><b>set_bb_depthlimit</b> has no return value.
</p>
<p class="label"><b>Parameters</b></p>
<p class="dt"><i>lp</i></p>
<p class="indent">Pointer to previously created lp model. See return value of <A href="make_lp.htm">
make_lp</A>, <A HREF="copy_lp.htm">copy_lp</A>, <A href="read_lp.htm">read_lp,
read_LP</A>, <A href="read_mps.htm">read_mps, read_freemps, read_MPS, read_freeMPS</A>, <A HREF="read_XLI.htm">read_XLI</A></p>
<p class="dt"><i>bb_maxlevel</i></p>
<p class="indent">
Specifies the maximum branch-and-bound depth. A positive value means that the depth
is absoluut. A negative value means a relative B&B depth limit.
The "order" of a MIP problem is defined to be 2x the number of binary variables plus
the number of SC and SOS variables.A relative value of -x results in a maximum
depth of x times the order of the MIP problem.</p>
<p class="label"><b>Remarks</b></p>
<p>The <b>set_bb_depthlimit</b> function sets the maximum branch-and-bound depth.<br>
This is only useful if there are integer, semi-continious or SOS variables in
the model so that the branch-and-bound algorithm must be used to solve them.
The branch-and-bound algorithm will not go deeper than this level. When 0 then
there is no limit to the depth. Limiting the depth will speed up solving time,
but there is a chance that the found solution is not the most optimal one. Be
aware of this. It can also result in not finding a solution at all.
<br>
The default is -50.
</p>
<p class="label"><b>Example</b></p>
<pre><code>#include <stdio.h>
#include <stdlib.h>
#include "lp_lib.h"
int main(void)
{
lprec *lp;
/* Create a new LP model */
lp = make_lp(0, 0);
if(lp == NULL) {
fprintf(stderr, "Unable to create new LP model\n");
return(1);
}
set_bb_depthlimit(lp, 10);
delete_lp(lp);
return(0);
}
</code></pre>
<p>
<A HREF="lp_solveAPIreference.htm">lp_solve API reference</A></p>
<p>
<b>See Also</b> <A HREF="make_lp.htm">make_lp</A>, <A HREF="copy_lp.htm">copy_lp</A>,
<A href="read_lp.htm">read_lp, read_LP</A>, <A HREF="read_mps.htm">read_mps,
read_freemps, read_MPS, read_freeMPS</A>, <A HREF="read_XLI.htm">read_XLI</A>, <A HREF="get_bb_depthlimit.htm">get_bb_depthlimit</A></p>
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