[Symphony] Issue: get No solution in Symphony

[Vladyslav Kolbasin]

Good Day! 

 I'm using RSymphony (package that uses Symphony for R).

I'm running rather large LP problems : about 1000-3000 variables and
800-2000 constraints. 

 For some my test-cases i get return code 226
(NO_SOLUTION). But i know that there are simple solutions and may be
rather complex too. 

 I set param verbosity to 140 and get such return:


Skipping Preprocessor
Problem has
 834 constraints
 1065 variables

4366 nonzero coefficients

Solving...

granularity set at 0.000001

TM:
tree size: 0 , 0

****************************************************
*
Now processing NODE 0 LEVEL 0 (from
TM)
****************************************************

Diving set to
2

**** Starting iteration 1 ****

solving root lp
relaxation
Terminating due to high cost -- fathoming node (no more cols
to check)

****************************************************
* Branch
and Cut Finished *
* Now displaying stats and best solution found...
*
****************************************************
..... 

 Also if
i do some mixing constraints & variables then get solution - it is most
strange issue. 

 Please Can you help me:
- explain why i can't get
solution
- advise any params (or may be combination) that can help me to
get any solution (already tryed some from "LP parameters" and some
others) 

Thanks a lot.

 
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Skipping Preprocessor
Problem has
         834 constraints
         1065 variables
         4366 nonzero coefficients

Solving...

granularity set at 0.000001

TM: tree size: 0 , 0

****************************************************
* Now processing NODE 0 LEVEL 0 (from TM)
****************************************************

Diving set to 2



**** Starting iteration 1 ****

solving root lp relaxation
Terminating due to high cost -- fathoming node (no more cols to check)


****************************************************
* Branch and Cut Finished                          *
* Now displaying stats and best solution found...  *
****************************************************

======================= CP Timing ===========================
  Cut Pool                  0.000
====================== LP/CG Timing =========================
  LP Solution Time          0.068
  LP Setup Time             0.000
  Variable Fixing           0.000
  Pricing                   0.000
  Strong Branching          0.000
  Separation                0.000
  Primal Heuristics         0.000
  Communication             0.004
  Total User Time              0.072
  Total Wallclock Time         0.075

====================== Statistics =========================
Number of created nodes :       1
Number of analyzed nodes:       1
Depth of tree:                  0
Size of the tree:               1
Number of solutions found:      0
Number of solutions in pool:    0
Number of Chains:               1
Number of Diving Halts:         0
Number of cuts in cut pool:     0

======================= LP Solver =========================
Number of times LP solver called:               1
Number of calls from feasibility pump:          0
Number of calls from strong branching:          0
Number of solutions found by LP solve:          0
Number of bounds changed by strong branching:   0
Number of nodes pruned by strong branching:     0

==================== Feasibility Pump =====================
Number of times feasibility pump called:        0
Number of solutions found by feasibility pump:  0
Time spent in feasibility pump:                 0.00

=========================== Cuts ==========================
total cuts accepted:                   0
total cuts added to LPs:               0
total cuts deleted from LPs:           0
total gomory cuts generated:           0
total knapsack cuts generated:         0
total oddhole cuts generated:          0
total clique cuts generated:           0
total probing cuts generated:          0
total mir cuts generated:              0
total twomir cuts generated:           0
total flow and cover cuts generated:   0
total rounding cuts generated:         0
total lift and project cuts generated: 0
total landp cuts generated:            0

cuts removed because of bad coeffs:    0
cuts removed because of duplicacy:     0
insufficiently violated cuts:          0

cuts in root:                          0
gomory cuts in root:                   0
knapsack cuts in root:                 0
oddhole cuts in root:                  0
clique cuts in root:                   0
probing cuts in root:                  0
mir cuts in root:                      0
twomir cuts in root:                   0
flow and cover cuts in root:           0
rounding cuts in root:                 0
lift and project cuts in root:         0
landp cuts in root:                    0

time in cut generation: 0.00
time in gomory cuts in 0 calls: 0.00
time in knapsack cuts in 0 calls: 0.00
time in oddhole cuts in 0 calls: 0.00
time in clique cuts in 0 calls: 0.00
time in probing cuts in 0 calls: 0.00
time in mir cuts in 0 calls: 0.00
time in twomir cuts in 0 calls: 0.00
time in flow and cover cuts in 0 calls: 0.00
time in rounding cuts in 0 calls: 0.00
time in lift and project cuts in 0 calls: 0.00
time in landp cuts in 0 calls: 0.00
time in redsplit cuts in 0 calls: 0.00
time in checking quality and adding: 0.00

Current Lower Bound:         0.000

The problem is infeasible!
No Solution Found

sym_get_col_solution(): There is no solution!
sym_get_obj_val(): There is no solution!