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<h1>set_improve</h1>
<p>Specifies the iterative improvement level.</p>
<p><b>void set_improve(lprec </b>*<i>lp</i><b>, int </b><i>improve</i><b>);</b></p>
<p class="label"><b>Return Value</b></p>
<p><b>set_improve</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>improve</i></p>
<p class="indent">Specifies the iterative improvement level. Can by any of the
following values:</p>
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<TD>IMPROVE_NONE (0)</TD>
<TD>improve none</TD>
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<TD>IMPROVE_SOLUTION (1)</TD>
<TD>Running accuracy measurement of solved equations based on Bx=r (primal simplex), remedy is refactorization.</TD>
</TR>
<TR>
<TD>IMPROVE_DUALFEAS (2)</TD>
<TD>Improve initial dual feasibility by bound flips (highly recommended, and default)</TD>
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<TR>
<TD>IMPROVE_THETAGAP (4)</TD>
<TD>Low-cost accuracy monitoring in the dual, remedy is refactorization</TD>
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<TD>IMPROVE_BBSIMPLEX (8)</TD>
<TD>By default there is a check for primal/dual feasibility at optimum only for the relaxed problem, this also activates the test at the node level</TD>
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<br>
<p class="label"><b>Remarks</b></p>
<p><p>The default is IMPROVE_DUALFEAS + IMPROVE_THETAGAP (6).
</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_improve(lp, IMPROVE_DUALFEAS | IMPROVE_BBSIMPLEX);
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_improve.htm">get_improve</A></p>
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