Dear all,
I am running a GLPK model that is sequentially started from a frame
program in Java.
The frame program does the following:
-It creates data files (.csv) that are read in by the GLPK model thereafter
-The call of the GLPK model is according to the help documentation:
/public void start() {
glp_prob lp = null;
glp_tran tran;
glp_iocp iocp;
int skip = 0;
int ret;
// GlpkCallback.addListener(this);
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);
// 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);
}
}/
The GKLP model writes some output tables (csv.), and the results are
read in again by Java after terminating the optimization run, and so on.
Unfortunately, I get sometime error when opening the .csv files.
Here is an example:
/
csv_driver: unable to open BOM.csv - Permission denied
allocation.mod:113: error on opening table tab_BOM
glp_mpl_build_prob: invalid call sequence
Error detected in file ..\src\glpapi14.c at line 93/
I do not get this error at each call of the Java model (one error after
approx. 50 calls). Moreover, these errors do not occur in a
deterministic manner, they cannot be reproduced. I each run of the Java
program they occur at another place.
Do you have any advice what I could do about that?
Many thanks for your effort.
Best regards
Martin
_______________________________________________
Help-glpk mailing list
[email protected]
https://lists.gnu.org/mailman/listinfo/help-glpk
