Re: [Help-glpk] Error when generating lp file

[Marcos Roberto Silva]

OK, it worked!!

Thanks a lot.

Marcos

2016-02-24 13:03 GMT-03:00 Andrew Makhorin <address@hidden>:

> I'm trying to generate a lp file from my model written in GMPL but I
> got the following error message:
>
>
> GLPSOL: GLPK LP/MIP Solver, v4.55
>
> Parameter(s) specified in the command line:
>
> -m usaphmcp-c.mod -d 100-15-c.dat --check --wcpxlp 100-15-c.lp
>
> Reading model section from usaphmcp-c.mod...
>
> 29 lines were read
>
> Reading data section from 100-15-c.dat...
>
> 215 lines were read
>
> Generating obj...
>
> Generating r1...
>
> Generating r2...
>
> Generating r3...
>
> Generating r4...
>
> Generating r5...
>
> Generating r6...
>
> Generating r7...
>
> Model has been successfully generated
>
> glp_add_rows: nrs = 300030002; too many rows
>
> Error detected in file glpapi01.c at line 256
>
>
> There is a size limit ?
>
>
Yes. There are the following limits (see glpk/src/glpapi01.c):

#define M_MAX 100000000 /* = 100*10^6 */
/* maximal number of rows in the problem object */

#define N_MAX 100000000 /* = 100*10^6 */
/* maximal number of columns in the problem object */

#define NNZ_MAX 500000000 /* = 500*10^6 */
/* maximal number of constraint coefficients in the problem object */

These limits are used mainly to avoid indexing overflow, because glpk
routines use the int type for array indices.

You may try to increase these limits. Please note, however, that most
probably glpk is unable to solve such huge instances; but if you only
need to generate the instance, this may work.


Andrew Makhorin