CPXXcopylp and CPXcopylp

The routine CPXXcopylp/CPXcopylp copies data that define an LP problem to a CPLEX problem object.

int CPXXcopylp( CPXCENVptr env, CPXLPptr lp, CPXDIM numcols, CPXDIM numrows, int objsense, double const * objective, double const * rhs, char const * sense, CPXNNZ const * matbeg, CPXDIM const * matcnt, CPXDIM const * matind, double const * matval, double const * lb, double const * ub, double const * rngval )

int CPXcopylp( CPXCENVptr env, CPXLPptr lp, int numcols, int numrows, int objsense, double const * objective, double const * rhs, char const * sense, int const * matbeg, int const * matcnt, int const * matind, double const * matval, double const * lb, double const * ub, double const * rngval )

Description

The routine CPXXcopylp/CPXcopylp copies data that define an LP problem to a CPLEX problem object. The arguments to CPXXcopylp/CPXcopylp define an objective function, the constraint matrix, the righthand side, and the bounds on the variables. Calling CPXXcopylp/CPXcopylp destroys any existing data associated with the problem object.

The routine CPXXcopylp/CPXcopylp does not copy names. The more comprehensive routine CPXXcopylpwnames/CPXcopylpwnames can be used in place of CPXXcopylp/CPXcopylp to copy linear programs with associated names.

The arguments passed to CPXXcopylp/CPXcopylp define a linear program. Since these arguments are copied into local arrays maintained by CPLEX, the LP problem data passed via CPXXcopylp/CPXcopylp may be modified or freed after the call to CPXXcopylp/CPXcopylp without affecting the state of the CPLEX problem object.

Table 1. Values of objsense
`objsense`	= `1`	(`CPX_MIN`) minimize
`objsense`	= `-1`	(`CPX_MAX`) maximize

Table 2. Values of sense
`sense[i]`	`'L'`	<= constraint
`sense[i]`	`'E'`	= constraint
`sense[i]`	`'G'`	>= constraint
`sense[i]`	`'R'`	ranged constraint

The arrays matbeg, matcnt, matind, and matval are accessed as follows. Suppose that CPLEX wants to access the entries in some column j. These are assumed to be given by the array entries:


matval[matbeg[j]],.., matval[matbeg[j]+matcnt[j]-1]

The corresponding row indices are:


matind[matbeg[j]],.., matind[matbeg[j]+matcnt[j]-1]

Entries in matind are not required to be in row order. Duplicate entries in matind within a single column are not allowed. The length of the arrays matbeg and matind should be at least numcols. The length of arrays matind and matval should be at least matbeg[numcols-1]+matcnt[numcols-1].

The arrays matbeg and matcnt can be NULL if one of numcols or numrows is 0 (zero); that is, if one dimension the matrix is 0 (zero) and can not contain any coefficients.

When you build or modify your problem with this routine, you can verify that the results are as you intended by calling CPXcheckcopylp during application development.

Arguments

env: A pointer to the CPLEX environment as returned by CPXXopenCPLEX/CPXopenCPLEX.
lp: A pointer to a CPLEX problem object as returned by CPXXcreateprob/CPXcreateprob.
numcols: An integer that specifies the number of columns in the constraint matrix, or equivalently, the number of variables in the problem object.
numrows: An integer that specifies the number of rows in the constraint matrix, not including the objective function or bounds on the variables.
objsense: An integer that specifies whether the problem is a minimization or maximization problem.
objective: An array of length at least numcols containing the objective function coefficients.
rhs: An array of length at least numrows containing the righthand side value for each constraint in the constraint matrix.
sense: An array of length at least numrows containing the sense of each constraint in the constraint matrix.
matbeg: An array that with matval, matcnt, and matind defines the constraint matrix.
matcnt: An array that with matbeg, matval, and matind defines the constraint matrix.
matind: An array that with matbeg, matcnt, and matval defines the constraint matrix.
matval: An array that with matbeg, matcnt, and matind defines the constraint matrix. CPLEX needs to know only the nonzero coefficients. These are grouped by column in the array matval. The nonzero elements of every column must be stored in sequential locations in this array with matbeg[j] containing the index of the beginning of column j and matcnt[j] containing the number of entries in column j. The components of matbeg must be in ascending order. For each k, matind[k] specifies the row number of the corresponding coefficient, matval[k].
lb: An array of length at least numcols containing the lower bound on each of the variables. Any lower bound that is set to a value less than or equal to that of the constant -CPX_INFBOUND is treated as negative infinity. CPX_INFBOUND is defined in the header file cplex.h.
ub: An array of length at least numcols containing the upper bound on each of the variables. Any upper bound that is set to a value greater than or equal to that of the constant CPX_INFBOUND is treated as infinity. CPX_INFBOUND is defined in the header file cplex.h.
rngval: An array of length at least numrows containing the range value of each ranged constraint. Ranged rows are those designated by 'R' in the sense array. If the row is not ranged, the rngval array entry is ignored. If rngval[i] > 0, then row i activity is in [rhs[i],rhs[i]+rngval[i]], and if rngval[i] <= 0,then row i activity is in [rhs[i]+rngval[i],rhs[i]]. This argument may be NULL.

Return

The routine returns 0 (zero) if successful and nonzero if an error occurs.

Example


status = CPXcopylp (env, lp, numcols, numrows, objsen, obj, rhs,
	     sense, matbeg, matcnt, matind, matval, lb,
	     ub, rngval);

See also the example lpex1.c in the CPLEX User's Manual and in the standard distribution.