Glpk java and .mod file

Question

I've got a .mod file and I can run it in java(Using netbeans). The file gets data from another file .dat, because the guy who was developing it used GUSEK. Now we need to implement it in java, but i dont know how to put data in the K constant in the .mod file.

Doesn't matter the way, can be through database querys or file reading.

I dont know anything about math programming, i just need to add values to the already made glpk function.

Here's the .mod function:

# OPRE

set K;

param mc {k in K};
param phi {k in K};
param cman {k in K};
param ni {k in K};
param cesp;
param mf;

var x {k in K} binary;

minimize custo: sum {k in K} (mc[k]*phi[k]*(1-x[k]) + cman[k]*phi[k]*x[k]);

s.t. recursos: sum {k in K} (cman[k]*phi[k]*x[k]) - cesp <= 0;
s.t. ocorrencias: sum {k in K} (ni[k] + (1-x[k])*phi[k]) - mf <= 0;

end;

And here's the java code:

package br.com.genera.service.otimi;

import org.gnu.glpk.*;

public class Gmpl implements GlpkCallbackListener, GlpkTerminalListener {

    private boolean hookUsed = false;

    public static void main(String[] arg) {

        String[] nomeArquivo = new String[2];
        nomeArquivo[0] = "C:\\PodaEquipamento.mod";

        System.out.println(nomeArquivo[0]);
        GLPK.glp_java_set_numeric_locale("C");
        System.out.println(nomeArquivo[0]);
        new Gmpl().solve(nomeArquivo);
    }

    public void solve(String[] arg) {
        glp_prob lp = null;
        glp_tran tran;
        glp_iocp iocp;

        String fname;
        int skip = 0;
        int ret;

        // listen to callbacks
        GlpkCallback.addListener(this);
        // listen to terminal output
        GlpkTerminal.addListener(this);

        fname = arg[0];

        lp = GLPK.glp_create_prob();
        System.out.println("Problem created");
        tran = GLPK.glp_mpl_alloc_wksp();
        ret = GLPK.glp_mpl_read_model(tran, fname, skip);
        if (ret != 0) {
            GLPK.glp_mpl_free_wksp(tran);
            GLPK.glp_delete_prob(lp);
            throw new RuntimeException("Model file not found: " + fname);
        }

        // generate model
        GLPK.glp_mpl_generate(tran, null);
        // build model
        GLPK.glp_mpl_build_prob(tran, lp);
        // set solver parameters
        iocp = new glp_iocp();
        GLPK.glp_init_iocp(iocp);
        iocp.setPresolve(GLPKConstants.GLP_ON);

        // do not listen to output anymore
        GlpkTerminal.removeListener(this);
        // solve model
        ret = GLPK.glp_intopt(lp, iocp);
        // postsolve model
        if (ret == 0) {
            GLPK.glp_mpl_postsolve(tran, lp, GLPKConstants.GLP_MIP);
        }
        // free memory
        GLPK.glp_mpl_free_wksp(tran);
        GLPK.glp_delete_prob(lp);

        // do not listen for callbacks anymore
        GlpkCallback.removeListener(this);

        // check that the hook function has been used for terminal output.
        if (!hookUsed) {
            System.out.println("Error: The terminal output hook was not used.");
            System.exit(1);
        }
    }

    @Override
    public boolean output(String str) {
        hookUsed = true;
        System.out.print(str);
        return false;
    }

    @Override
    public void callback(glp_tree tree) {
        int reason = GLPK.glp_ios_reason(tree);
        if (reason == GLPKConstants.GLP_IBINGO) {
            System.out.println("Better solution found");
        }
    }
}

And i'm getting this in the console:

Reading model section from C:\PodaEquipamento.mod...
33 lines were read
Generating custo...
C:\PodaEquipamento.mod:24: no value for K
glp_mpl_build_prob: invalid call sequence

Hope someone can help, thanks.

Answer 1

I resolved just copying the data block from the .data file into the .mod file.

Anyway,Thanks puhgee.