Originally posted by: bm_omid

Hi I want to solve linear programming (LP) problem which has 25000 binary variables and almost 2555 equality constraints and 50 inequality constraints , so I used cplexbilp function which CPLEX API provided for MATLAB like this:

[x,fval,exitflag,output,] = cplexbilp(f, Aineq, bineq, Aeq, beq);

• size of the matrices: f=25000x1, Aineq=50x25000, bineq=50x1, Aeq=2555x25000, beq=2255x1

when I run the script, this error appears:

When I review the error details, I see this message:

0x6df51ba9 C:/Program Files/IBM/ILOG/CPLEX_Studio_Preview125/cplex/matlab/x86_win32/cplexlink125.mexw32+00007081 ( ???+000000 )

I think cplexlink125.mexw32 is cplex v12.5 callable library for MATLAB.
So, my question is how to solve this error? and I want to know is the problem size (25000 binary variables) main error root? I read in some resources that Cplex is able to solve large scale LP problems.

• MATLAB version: R2011a
• CPLEX version: 12.5 (Full Version)

Thanks in advance for any comment or answer

Your installation location contains CPLEX_Studio_Preview125. Are you sure that you installed the full version? Preview licenses are limited to several hundreds of variables/constraints and your problem dimensions exceed that limit.

Still, you should get an error message and not a crash. Could you provide your data here so that we can try to reproduce the issue?

Originally posted by: hllsen

I am getting the above screen from time to time (5-6 times a day if I use the MATLAB API). The following is not the most recent one but apparently I just kept this one for some reason (that I do not remember). By the way, these crashes are random in nature, I mean, after a MATLAB restart I could solve the same instance without any problems, every and each time one of these crashes occurred.

------------------------------------------------------------------------
          Access violation detected at Thu Nov 14 20:50:08 2013
------------------------------------------------------------------------

Configuration:
  Crash Decoding     : Disabled
  Default Encoding   : windows-1252
  MATLAB Architecture: win64
  MATLAB Root        : C:\Program Files\MATLAB\R2013b
  MATLAB Version     : 8.2.0.701 (R2013b)
  Operating System   : Microsoft Windows 8
  Processor ID       : x86 Family 6 Model 58 Stepping 9, GenuineIntel
  Virtual Machine    : Java 1.7.0_11-b21 with Oracle Corporation Java HotSpot(TM) 64-Bit Server VM mixed mode
  Window System      : Version 6.2 (Build 9200)

Fault Count: 1


Abnormal termination:
Access violation

Register State (from fault):
  RAX = 0000000000000000  RBX = 000000006b6a4730
  RCX = 000000006b6a4730  RDX = 000000007e87dd18
  RSP = 0000000004036710  RBP = 0000000004036920
  RSI = 000000006b6a4730  RDI = 000000007e87dd18
 
   R8 = 0000000000000001   R9 = 0000000000000000
  R10 = 00007fff94c40000  R11 = 0000000118bdeda0
  R12 = 0000000000000001  R13 = 0000000004037870
  R14 = 5f5e5d5c5b5a5958  R15 = 0000000000000000
 
  RIP = 00000000b1eaf5b8  EFL = 00010206
 
   CS = 0033   FS = 0053   GS = 002b

Stack Trace (from fault):
[  0] 0x00000000b1eaf5b8 C:\Program Files\IBM\ILOG\CPLEX_Studio1251\opl\bin\x64_win64\cplex1251.dll+00521656 CPXEinitcomp+00046264
[  1] 0x00000000b1ea6d37 C:\Program Files\IBM\ILOG\CPLEX_Studio1251\opl\bin\x64_win64\cplex1251.dll+00486711 CPXEinitcomp+00011319
[  2] 0x00000000b21296f3 C:\Program Files\IBM\ILOG\CPLEX_Studio1251\opl\bin\x64_win64\cplex1251.dll+03118835 CPXfreeprob+00000163
[  3] 0x00007fff8ddc2e3d C:\Program Files\IBM\ILOG\CPLEX_Studio1251\cplex\matlab\x64_win64\cplexlink1251.mexw64+00011837 mexFunction+00001917
[  4] 0x00007fff8ddc2863 C:\Program Files\IBM\ILOG\CPLEX_Studio1251\cplex\matlab\x64_win64\cplexlink1251.mexw64+00010339 mexFunction+00000419
....

This error was detected while a MEX-file was running. If the MEX-file
is not an official MathWorks function, please examine its source code
for errors. Please consult the External Interfaces Guide for information
on debugging MEX-files.