CplexOptimizer
class CplexOptimizer(disp=False)
The CPLEX optimizer wrapped as an Qiskit OptimizationAlgorithm.
This class provides a wrapper for cplex.Cplex (https://pypi.org/project/cplex/) to be used within the optimization module.
Examples
>>> from qiskit.optimization.problems import QuadraticProgram
>>> from qiskit.optimization.algorithms import CplexOptimizer
>>> problem = QuadraticProgram()
>>> # specify problem here, if cplex is installed
>>> optimizer = CplexOptimizer() if CplexOptimizer.is_cplex_installed() else None
>>> if optimizer: result = optimizer.solve(problem)Initializes the CplexOptimizer.
Parameters
disp (Optional[bool]) – Whether to print CPLEX output or not.
Raises
NameError – CPLEX is not installed.
Attributes
disp
Type: bool
Returns the display setting.
Return type
bool
Returns
Whether to print CPLEX information or not.
Methods
get_compatibility_msg
CplexOptimizer.get_compatibility_msg(problem)
Checks whether a given problem can be solved with this optimizer.
Returns '' since CPLEX accepts all problems that can be modeled using the QuadraticProgram. CPLEX may throw an exception in case the problem is determined to be non-convex.
Parameters
problem (QuadraticProgram) – The optimization problem to check compatibility.
Return type
str
Returns
An empty string.
is_compatible
CplexOptimizer.is_compatible(problem)
Checks whether a given problem can be solved with the optimizer implementing this method.
Parameters
problem (QuadraticProgram) – The optimization problem to check compatibility.
Return type
bool
Returns
Returns True if the problem is compatible, False otherwise.
is_cplex_installed
static CplexOptimizer.is_cplex_installed()
Returns True if cplex is installed
solve
CplexOptimizer.solve(problem)
Tries to solves the given problem using the optimizer.
Runs the optimizer to try to solve the optimization problem. If problem is not convex, this optimizer may raise an exception due to incompatibility, depending on the settings.
Parameters
problem (QuadraticProgram) – The problem to be solved.
Return type
OptimizationResult
Returns
The result of the optimizer applied to the problem.
Raises
QiskitOptimizationError – If the problem is incompatible with the optimizer.