CPXXuncrushform and CPXuncrushform

The routine CPXXuncrushform/CPXuncrushform uncrushes a linear formula of the presolved problem to a linear formula of the original problem.

int CPXXuncrushform( CPXCENVptr env, CPXCLPptr lp, CPXDIM plen, CPXDIM const * pind, double const * pval, CPXDIM * len_p, double * offset_p, CPXDIM * ind, double * val )

int CPXuncrushform( CPXCENVptr env, CPXCLPptr lp, int plen, int const * pind, double const * pval, int * len_p, double * offset_p, int * ind, double * val )

Description

Warning:

This is an advanced routine. Advanced routines typically demand a thorough understanding of the algorithms used by CPLEX. Thus they incur a higher risk of incorrect behavior in your application, behavior that can be difficult to debug. Therefore, the team encourages you to consider carefully whether you can accomplish the same task by means of other Callable Library routines instead.

The routine CPXXuncrushform/CPXuncrushform uncrushes a linear formula of the presolved problem to a linear formula of the original problem.

Let cols = CPXgetnumcols(env, lp). If ind[i] < cols then the i-th variable in the formula is the variable with index ind[i] in the original problem. If ind[i] >= cols, then the i-th variable in the formula is the slack for the (ind[i]-cols)-th ranged row. The arrays ind and val must be of length at least the number of columns plus the number of ranged rows in the original LP problem object.

Arguments

env: A pointer to the CPLEX environment, as returned by CPXXopenCPLEX/CPXopenCPLEX.
lp: A pointer to a CPLEX LP problem object, as returned by CPXXcreateprob/CPXcreateprob.
plen: The number of entries in the arrays pind and pval.
pind: An array containing the column indices of coefficients in the array pval.
pval: The linear formula in terms of the presolved problem. Each entry, pind[i], specifies the column index of the corresponding coefficient, pval[i].
len_p: A pointer to an integer to receive the number of nonzero coefficients, that is, the true length of the arrays ind and val.
offset_p: A pointer to a double to contain the value of the linear formula corresponding to variables that have been removed in the presolved problem.
ind: An array containing indices of coefficients in the array val.
val: The linear formula in terms of the original problem.

Return

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

Example


status = CPXuncrushform (env, lp, plen, pind, pval,
		  &len, &offset, ind, val);