e04rxc adds an additional means of communication to functions within the
NAG optimization modelling suite. It allows you to either read or write a piece of information in the handle in the form of a real array. The item is identified by
cmdstr and the direction of the communication is set by
ioflag.
The functionality is supported by all solvers within the
NAG optimization modelling suite for the retrieval of their final solutions.
e04rxc, moreover, can also be used by a selection of the solvers in the
NAG Library, such as,
e04mtc and
e04ptc for the retrieval of the approximate solutions within the monitoring step. See the documentation of the individual solvers. In addition, you can retrieve solutions from a specific solver by adding the solver name after the available
cmdstr mentioned above, e.g., keywords
X e04mt or
X handle_solve_lp_ipm return the value of primal variables only from the linear programming solver
e04mtc. This is useful when a problem is solved by several different solvers. See
Section 4.1 in the
E04 Chapter Introduction for more details about the
NAG optimization modelling suite.
None.
Not applicable.
Background information to multithreading can be found in the
Multithreading documentation.
Please consult the
X06 Chapter Introduction for information on how to control and interrogate the OpenMP environment used within this function. Please also consult the
Users' Note for your implementation for any additional implementation-specific information.
None.
This example demonstrates how to use
e04rxc to extract the current approximation of the solution when the monitoring function
monit is called during the solve by
e04mtc.
We solve the following linear programming problem:
subject to the bounds
and the general constraints
During the monitoring step of
e04mtc, if the three convergence measures are below an acceptable threshold, the approximate solution is extracted with
e04rxc and printed on the standard output.