Generates LP files for printing
CPLEX linear optimized XYZ network flow solutions,
where X and Z are source and destination nodes, respectively, and Y are transit nodes, with
constraints X >= Z > 0, Y > 2.
- CPLEX to formulate optimal network flow solutions using generated LP files.
To optimise multiple XYZ LP files, where X = Z = 7, Y = {3,...,7}:
python3 test.py
Alternatively, to optimise a single LP file:
python3 flow.py <X (int)> <Y (int)> <Z (int)>
Problem 'Y=7.lp' read.
Read time = 0.00 sec. (0.07 ticks)
Tried aggregator 2 times.
MIP Presolve eliminated 105 rows and 56 columns.
MIP Presolve modified 47 coefficients.
Aggregator did 392 substitutions.
Reduced MIP has 56 rows, 344 columns, and 693 nonzeros.
Reduced MIP has 343 binaries, 0 generals, 0 SOSs, and 0 indicators.
Presolve time = 0.00 sec. (1.24 ticks)
Found incumbent of value 130.666667 after 0.00 sec. (1.45 ticks)
Probing time = 0.00 sec. (0.20 ticks)
Cover probing fixed 0 vars, tightened 6 bounds.
Tried aggregator 1 time.
Reduced MIP has 56 rows, 344 columns, and 693 nonzeros.
Reduced MIP has 343 binaries, 0 generals, 0 SOSs, and 0 indicators.
Presolve time = 0.00 sec. (0.56 ticks)
Probing time = 0.00 sec. (0.05 ticks)
MIP emphasis: balance optimality and feasibility.
MIP search method: dynamic search.
Parallel mode: deterministic, using up to 8 threads.
Root relaxation solution time = 0.00 sec. (0.58 ticks)
Nodes Cuts/
Node Left Objective IInf Best Integer Best Bound ItCnt Gap
* 0+ 0 130.6667 4.6667 96.43%
0 0 56.0000 10 130.6667 56.0000 92 57.14%
* 0+ 0 58.0000 56.0000 3.45%
0 0 56.0000 14 58.0000 Cuts: 14 101 3.45%
* 0+ 0 57.6667 56.0000 2.89%
0 0 56.0000 15 57.6667 Cuts: 7 112 2.89%
* 0+ 0 57.3333 56.0000 2.33%
* 0+ 0 57.0000 56.0000 1.75%
* 0+ 0 56.3333 56.0000 0.59%
* 0+ 0 56.0000 56.0000 0.00%
0 0 cutoff 56.0000 56.0000 112 0.00%
Elapsed time = 0.07 sec. (21.25 ticks, tree = 0.01 MB, solutions = 7)
Root node processing (before b&c):
Real time = 0.07 sec. (21.32 ticks)
Parallel b&c, 8 threads:
Real time = 0.00 sec. (0.00 ticks)
Sync time (average) = 0.00 sec.
Wait time (average) = 0.00 sec.
------------
Total (root+branch&cut) = 0.07 sec. (21.32 ticks)
Solution pool: 7 solutions saved.
MIP - Integer optimal solution: Objective = 5.6000000000e+01
Solution time = 0.07 sec. Iterations = 112 Nodes = 0
Deterministic time = 21.32 ticks (306.31 ticks/sec)
Incumbent solution
Variable Name Solution Value
r 56.000000
xI1K1J1 0.666667
...
lK7 56.000000
All other variables in the range 1-792 are 0.