[Help-glpk] problem with lpx_read_model

[address@hidden]

Dear all,

I am trying the following code in C++:

  glp_prob *mip;
  mip = glp_create_prob();
  lpx_read_model("model.mod", "data.dat", "output.out");
  lpx_simplex(mip);
  lpx_integer(mip);
  lpx_print_prob(mip, "problem.dat");

The program runs without errors and gives:
Reading model section from Mode.mod...
38 lines were read
Reading data section from data.dat...
67 lines were read
Generating cost...
Generating traffic....
(et cetera)
Model has been successfully created
~   0: objval = 0.000000e+000 infeas = 0.0000000e+000
OPTIMAL SOLUTION FOUND
Integer optimization begins...
(et cetera)

Which should not be the case, for some reason, both the model and data is
not read correctly.

problem.dat gives:
Problem:    (unnamed)
Class:      LP
Rows:       0
Columns:    0
Non-zeros:  0

*** OBJECTIVE FUNCTION ***

Minimize: (unnamed)

*** ROWS (CONSTRAINTS) ***

*** COLUMNS (VARIABLES) ***

End of output

output.out is completely empty.

Does anyone have any idea?

The reason I want to use C++ is to solve the problem for different
datasets, furthermore I wish to find the total number of nodes in the
branch and bound tree. Do I need to use control parameters and store
information on every branch for that or is there an easier way to get the
total number of examined nodes?

Thanks,


Timo




--------------------------------------------------------------------
myhosting.com - Premium Microsoft® Windows® and Linux web and application
hosting - http://link.myhosting.com/myhosting