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<h1>get_primal_solution, get_ptr_primal_solution, get_var_primalresult</h1>
<p>Returns the solution of the model.</p>
<p><b>unsigned char get_primal_solution(lprec </b>*<i>lp</i><b>, REAL </b>*<i>pv</i><b>);</b></p>
<p><b>unsigned char get_ptr_primal_solution(lprec </b>*<i>lp</i><b>, REAL </b>**<i>ptr_pv</i><b>);</b></p>
<p><b>REAL get_var_primalresult(lprec </b>*<i>lp</i><b>, int </b><i>index</i><b>);</b></p>
<p class="label"><b>Return Value</b></p>
<p><b>get_primal_solution, get_ptr_primal_solution</b> return TRUE (1) if the
operation was successful. A return value of FALSE (0) indicates an error.<br>
<b>get_var_primalresult</b> returns the value for <i>index</i>.
</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>pv</i></p>
<p class="indent">An array that will contain the value of the objective function
(element 0), values of the constraints (elements 1 till Nrows), and the values
of the variables (elements Nrows+1 till Nrows+NColumns).</p>
<p class="dt"><i>ptr_pv</i></p>
<p class="indent">The address of a pointer that will point to an array that will
contain the value of the objective function (element 0), values of the
constraints (elements 1 till Nrows), and the values of the variables (elements
Nrows+1 till Nrows+NColumns).</p>
<p class="dt"><i>index</i></p>
<p class="indent">index of the constraint/variable.</p>
<p class="label"><b>Remarks</b></p>
<p>The <b>get_primal_solution</b>, <b>get_ptr_primal_solution</b>, <b>get_var_primalresult</b>
functions retrieve the values of the objective function, constraints and
variables.<br>
These values are only valid after a successful <A href="solve.htm">solve</A> or <A href="lag_solve.htm">
lag_solve</A>. Function <b>get_primal_solution</b> needs an array that is
already dimensioned with 1+<A href="get_Nrows.htm">get_Nrows</A> + <A href="get_Ncolumns.htm">
get_Ncolumns</A> elements. <b>get_ptr_primal_solution</b> returns a pointer
to an array already dimensioned by lp_solve. Element 0 is the value of the
objective function, elements 1 till Nrows the values of the constraints and
elements Nrows+1 till Nrows+NColumns the values of the variables.
<i>get_var_primalresult</i> requires no array.
<i>index</i> is the array element number of the above functions and returns the value for
this array element.<br>
Special considerations when presolve was done. When <A href="set_presolve.htm">set_presolve</A>
is called before <A href="solve.htm">solve</A>, then presolve can have deleted both rows
and columns from the model because they could be eliminated.
This influences <b>get_primal_solution</b> and <b>get_ptr_primal_solution</b>. These
functions only report the values of the remaining variables and constraints. However
<b>get_var_primalresult</b> returns all values, also the deleted ones by presolve.
So <i>index</i> is the original index number as known by the caller.
</p>
<p>Note that <b>get_ptr_primal_solution</b> returns a pointer to memory allocated and maintained
by lp_solve. Be careful what you do with it. Don't modify its contents or free the memory.
Unexpected behaviour would occur. Also note that this memory pointer is only guaranteed to
remain constant until a next lp_solve API call is done. You should call this function again
to make sure you have again the correct pointer. Otherwise, this pointer could point to invalid
memory. This should not be a problem since this call is very efficient.</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;
REAL pv[1+2+3], *ptr_pv;
/* Create a new LP model */
lp = make_lp(3, 2);
if(lp == NULL) {
fprintf(stderr, "Unable to create new LP model\n");
return(1);
}
solve(lp);
get_primal_solution(lp, pv);
get_ptr_primal_solution(lp, &ptr_pv);
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="is_feasible.htm">is_feasible</a>, <A HREF="get_objective.htm">
get_objective</A>, <A HREF="get_working_objective.htm">get_working_objective</A>, <a href="get_variables.htm">get_variables, get_ptr_variables</a>,
<a href="get_constraints.htm">get_constraints, get_ptr_constraints</a>, <a href="get_constr_value.htm">get_constr_value</a>, <a href="get_sensitivity_rhs.htm">
get_sensitivity_rhs, get_ptr_sensitivity_rhs, get_dual_solution,
get_ptr_dual_solution, get_var_dualresult</a>, <a href="get_sensitivity_obj.htm">
get_sensitivity_obj, get_ptr_sensitivity_obj, get_sensitivity_objex,
get_ptr_sensitivity_objex</a>
</p>
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