get_bb_depthlimit
Returns the maximum branch-and-bound depth.
int get_bb_depthlimit(lprec *lp);
Return Value
get_bb_depthlimit returns the maximum branch-and-bound depth.
Parameters
lp
Pointer to previously created lp model. See return value of
make_lp, copy_lp, read_lp,
read_LP, read_mps, read_freemps, read_MPS, read_freeMPS, read_XLI
Remarks
The get_bb_depthlimit function returns the maximum branch-and-bound
depth.
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.
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.
The default is -50.
Example
#include <stdio.h>
#include <stdlib.h>
#include "lp_lib.h"
int main(void)
{
lprec *lp;
int bb_maxlevel;
/* Create a new LP model */
lp = make_lp(0, 0);
if(lp == NULL) {
fprintf(stderr, "Unable to create new LP model\n");
return(1);
}
bb_maxlevel = get_bb_depthlimit(lp);
delete_lp(lp);
return(0);
}
lp_solve API reference
See Also make_lp, copy_lp,
read_lp, read_LP, read_mps,
read_freemps, read_MPS, read_freeMPS, read_XLI, set_bb_depthlimit
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