The LP Procedure

RESET Statement

  • RESET options;

The RESET statement is used to change options after the LP procedure has started execution.

All of the options that can be set in the PROC LP statement can also be reset with the RESET statement, except for the DATA= , the PRIMALIN= , and the ACTIVEIN= options. In addition to the options available with the PROC LP statement, the following two options can be used.

LOWER(colnames)=n;

During phase 3, this sets the lower bound on all of the structural variables listed in the colnames list to an integer value n. This may contaminate the branch-and-bound tree. All nodes that descend from the current problem have lower bounds that may be different from those input in the problem data set.

UPPER(colnames)=n;

During phase 3, this sets the upper bound on all of the structural variables listed in the colnames list to an integer value n. This may contaminate the branch-and-bound tree. All nodes that descend from the current problem have upper bounds that may be different from those input in the problem data set.

Note that the LOWER= and UPPER= options only apply to phase 3 for integer problems. Therefore, they should only be applied once the integer iterations have started; if they are applied before then, they will be ignored.