Re: [Help-glpk] Can't read CPLEX file
On 06/03/06, Andrew Makhorin [EMAIL PROTECTED] wrote: I currently have GLPK 4.9 installed and the following CPLEX file: maximize 1 st - 2 x1 - 3 x2 = -1 2 x1 + 3 x2 = 1 - 1 x1 - 1 x2 = -4 1 x1 + 1 x2 = 4 bounds x1 free x2 free end Cplex can read it. glpsolve: $ glpsol --cpxlp test.lp lpx_read_cpxlp: reading problem data from `test.lp'... test.lp:2: missing variable name CPLEX LP file processing error Why? Because there is a syntax error in maximize statement. Note that glpk does not support some features allowed in recent versions of cplex format, in particular, constant terms in the objective. For details about compatibility please consult the glpk reference manual (Appendix C CPLEX LP Format, pp.79-84). If you need only a feasible solution, simply specify any variable as the objective, for example: maximize x1 Thanks, and is it possible to have it output the solution found? I searched --help flag but found nothing. Paulo Matos -- Paulo Jorge Matos - pocm at sat inesc-id pt Web: http://sat.inesc-id.pt/~pocm Computer and Software Engineering INESC-ID - SAT Group ___ Help-glpk mailing list Help-glpk@gnu.org http://lists.gnu.org/mailman/listinfo/help-glpk
Re: [Help-glpk] Can't read CPLEX file
Thanks, and is it possible to have it output the solution found? I searched --help flag but found nothing. To write the solution into a file for further browsing use the option '-o filename'. P.S. Another, more correct way to specify a dummy objective in cplex lp format is the following: minimize foo; ... bounds ... foo = 0 ... ___ Help-glpk mailing list Help-glpk@gnu.org http://lists.gnu.org/mailman/listinfo/help-glpk
Re: [Help-glpk] Can't read CPLEX file
I currently have GLPK 4.9 installed and the following CPLEX file: maximize 1 st - 2 x1 - 3 x2 = -1 2 x1 + 3 x2 = 1 - 1 x1 - 1 x2 = -4 1 x1 + 1 x2 = 4 bounds x1 free x2 free end Cplex can read it. glpsolve: $ glpsol --cpxlp test.lp lpx_read_cpxlp: reading problem data from `test.lp'... test.lp:2: missing variable name CPLEX LP file processing error Why? Because there is a syntax error in maximize statement. Note that glpk does not support some features allowed in recent versions of cplex format, in particular, constant terms in the objective. For details about compatibility please consult the glpk reference manual (Appendix C CPLEX LP Format, pp.79-84). If you need only a feasible solution, simply specify any variable as the objective, for example: maximize x1 ___ Help-glpk mailing list Help-glpk@gnu.org http://lists.gnu.org/mailman/listinfo/help-glpk
