Populating the problem object

Your Callable Library application populates the problem object with data.

The problem object instantiated by CPXcreateprob represents an empty problem that contains no data; it has zero constraints, zero variables, and an empty constraint matrix. This empty problem object must be populated with data. This step can be carried out in several ways.

• The problem object can be populated by assembling arrays of data and then calling CPXcopylp to copy the data into the problem object. (For example, see Building and solving a small LP model in C.)

• Alternatively, you can populate the problem object by sequences of calls to the routines CPXnewcols, CPXnewrows, CPXaddcols, CPXaddrows, and CPXchgcoeflist ; these routines may be called in any order that is convenient. (For example, see Adding rows to a problem: example lpex3.c.)

• If the data already exist in a file using MPS format or LP format, you can use CPXreadcopyprob to read the file and copy the data into the problem object. (For example, see Reading a problem from a file: example lpex2.c.)