Purpose
Load a
MIP solution into the optimizer.
Synopsis
function loadmipsol(s:array(set of mpvar) of real):integer
function loadmipsol(solnum:integer):integer
Arguments
s

An array containing the solution

solnum

Solution number (between 1 and XPRS_enumsols)

Return value
Operation status:
1

Solution rejected because an error occurred

0

Solution accepted

1

Solution rejected because it is infeasible

2

Solution rejected because it is cut off

3

Solution rejected because the LP reoptimization was interrupted

Example
The following saves a MIP solution, modifies the problem, and then loads
it into the Optimizer, reloading the MIP solution:
declarations
MinCost:linctr
mysol: array(set of mpvar) of real
result: integer
enddeclarations
savemipsol(mysol)
... ! Make some changes
loadprob(MinCost)
result:= loadmipsol(mysol)
if result<>0 then writeln("Loading MIP solution failed"); endif
minimize(MinCost)
Further information
1. This function loads a MIP solution into the optimizer that has
previously been saved using procedure
savemipsol or
constructed by some external heuristic. In the latter case a value needs
to be assigned to each discrete variable in the problem, such as
mysol(x):= 1 (where
x is a decision variable of type
mpvar).
2. The values for the continuous variables in the s array are
ignored and are calculated by fixing the integer variables and
reoptimizing.
3.
The second form of the routine can be called after a search for nbest solutions
has been performed by the optimiser: the selected solution is used
as input.
4. The current problem definition must be loaded into the Optimizer for
loadmipsol to have any effect. If this has not recently been
done,
e.g., by calling
maximize or
minimize, the problem must be explicitly loaded using
loadprob.
5. If the MIP solution is accepted by the Optimizer it causes the
MIPABSCUTOFF control to be set accordingly. The provided MIP
solution may help guiding
the MIP heuristics but the branchandbound search will start from the
initial LP relaxation solution as usual.
Related topics
Module
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