CPXXreadcopystartinfo and CPXreadcopystartinfo

The routine CPXXreadcopystartinfo/CPXreadcopystartinfo reads start information from a SOL format file, and copies that basis or solution into a CPLEX problem object.

int  CPXXreadcopystartinfo( CPXCENVptr env, CPXLPptr lp, char const * filename_str )

int  CPXreadcopystartinfo( CPXCENVptr env, CPXLPptr lp, char const * filename_str )

Description

The routine CPXXreadcopystartinfo/CPXreadcopystartinfo reads start information from a SOL format file, and copies that basis or solution into a CPLEX problem object. The solution is used to initiate a crossover from a barrier solution, to restart the simplex method with an advanced basis, or to specify variable values for a MIP start. The file may contain basis status values, primal values, dual values, or a combination of those values.

The parameter known as the advanced start switch (CPXPARAM_Advance) must be set to 1 (one), its default value, or 2 (two) in order for the start to be used for starting a subsequent optimization.

The SOL format is an XML format and is documented in the stylesheet solution.xsl and schema solution.xsd in the include directory of the CPLEX distribution. CPLEX File Formats Reference Manual also documents this format briefly.

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.
filename_str
The name of the SOL format file from which the start information should be read.

Return

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

Example


status = CPXreadcopystartinfo (env, lp, "myprob.sol");