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<h1>set_obj_bound</h1>
<p>Set initial "at least better than" guess for objective function.</p>
<p><b>void set_obj_bound(lprec </b>*<i>lp</i><b>, REAL </b><i>obj_bound</i><b>);</b></p>
<p class="label"><b>Return Value</b></p>
<p><b>set_obj_bound</b> has no return value.<br>
</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>obj_bound</i></p>
<p class="indent">The initial "at least better than" guess for objective function.
</p>
<b>Remarks</b>
<p>The <b>set_obj_bound</b> function specifies the initial "at least better than"
guess for objective function. This is only used in the branch-and-bound
algorithm when integer variables exist in the model. All solutions with a worse
objective value than this value are immediately rejected. This can result in
faster solving times, but it can be difficult to predict what value to take for
this bound. Also there is the chance that the found solution is not the most
optimal one.<br>
The default is infinite.
</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_obj_bound(lp, 1000);
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_obj_bound.htm">get_obj_bound</A>, , <A HREF="set_break_at_value.htm">
set_break_at_value</A>, <A HREF="get_break_at_value.htm">get_break_at_value</A>
<A HREF="set_mip_gap.htm">set_mip_gap</A>, <A HREF="get_mip_gap.htm">get_mip_gap</A></p>
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