OptimizationProblem (JOM (Java Optimization Modeler) 0.3.2 API)

java.lang.Object
- com.jom.OptimizationProblem

```
public class OptimizationProblem
extends Object
```
This class contains the methods for handling optimization problems, defining their input parameters (if any), decision variables, objetive function and constraints, choosing and calling a solver to obtain a numerical solution, and retrieving that solution.

Author:

Pablo Pavon Mariño

See Also:

http://www.net2plan.com/jom

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class OptimizationProblem.JOMSolver

Nested Classes
Modifier and Type	Class and Description
`static class`	`OptimizationProblem.JOMSolver`

Constructor Summary

Constructors
Constructor and Description

OptimizationProblem()
Creates an optimization problem object

Constructors
Constructor and Description
`OptimizationProblem()` Creates an optimization problem object

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`String`	`about()` Returns an informative string about the JOM library
`Expression`	`addConstraint(String expression)` Adds (an array of) constraints to the optimization problem.
`Expression`	`addConstraint(String expression, String identifier)` Adds (an array of) constraints to the optimization problem.
`void`	`addDecisionVariable(String name, boolean isInteger, int[] size)` Same as addDecisionVariable(name, isInteger, size, null, null);
`void`	`addDecisionVariable(String name, boolean isInteger, int[] size, double[] x_l, double[] x_u)` Adds an array of decision variables to the optimization problem
`void`	`addDecisionVariable(String name, boolean isInteger, int[] size, double x_l, double x_u)` addDecisionVariable(String name, boolean isInteger, int[] size, DoubleMatrixND x_l, DoubleMatrixND x_u), but now the lower (upper) bounds for all the decision variables in the array are equal to x_l (x_u).
`void`	`addDecisionVariable(String name, boolean isInteger, int[] size, DoubleMatrix1D x_l, DoubleMatrix1D x_u)` Adds an array of decision variables to the optimization problem
`void`	`addDecisionVariable(String name, boolean isInteger, int[] size, DoubleMatrixND x_l, DoubleMatrixND x_u)` Adds an array of decision variables to the optimization problem
`boolean`	`feasibleSolutionDoesNotExist()` Returns true if the problem was attempted to be solved, and the solver declares that the problem has no feasible solutions.
`boolean`	`foundUnboundedSolution()` Returns true if the problem was attempted to be solved, and the solver declares that the problem is unbounded.
`static List<String>`	`getAcceptedSolverNames()` Returns the list of the names of the installed solvers, in the form that is accepted as the solverName inpt parameter of solve method
`double`	`getBestOptimalityBound()` Returns the best optimality bound found by the solver.
`DoubleMatrixND`	`getInputParameter(String name)` Obtains the value (an array of doubles) of the input parameter previously set
`DoubleMatrixND`	`getMultiplierOfLowerBoundConstraintToPrimalVariables(String decisionVariableName)` Returns the multipliers of the automatic constraints: \(x_l \leq varName\) added to the problem, where \(x_l\) is the array of lower bounds provided, associated to the decision variable.
`DoubleMatrixND`	`getMultiplierOfUpperBoundConstraintToPrimalVariables(String decisionVariableName)` Returns the multipliers of the automatic constraints: \(varName \leq x_u\) added to the problem, where \(x_u\) is the array of upper bounds provided, associated to the decision variable.
`DoubleMatrixND`	`getMultipliersOfConstraint(String constraintIdentifier)` Returns the multipliers of the given constraint
`int`	`getNumLinearScalarConstraints()` Gets the number of scalar constraints in the problem that are linear (with integer variables or not).
`int`	`getNumNonLinearScalarConstraints()` Gets the number of scalar constraints in the problem that are non linear (with integer variables or not).
`int`	`getNumScalarDecisionVariables()` Gets the number of scalar decision variables.
`Expression`	`getObjectiveFunction()` Gets the objective function expression set in the problem
`double`	`getOptimalCost()` Returns the cost of the solution obtained by the solver
`DoubleMatrixND`	`getPrimalSolution(String decisionVariable)` Returns the primal solution obtained after solving the problem for the given (array of) decision variables.
`DoubleMatrixND`	`getSlackOfConstraint(String constraintIdentifier)` Returns the slack of the given constraints.
`boolean`	`hasConstraint(String identifier)` Indicates if a constraint set with the given identifier exists in the model
`boolean`	`hasDecisionVariable(String identifier)` Indicates if a decision variable with the given identifier exists in the model
`boolean`	`isInputParameter(String name)` Returns true if the given name corresponds to an input parameter defined for the problem
`boolean`	`isIntegerProblem()` Returns true if the problem has one or more decision variables constrained to be integer, false otherwise
`boolean`	`isLinearProblem()` Returns true if the problem is linear (with some/all integer variables or not).
`boolean`	`isToMinimize()` Returns true if the current objective function has already been defined, and the problem is set as a minimization problem
`Expression`	`parseExpression(String expression)` Help function (not needed usually for solving optimization problems) to generate an Expression object from its String representation.
`boolean`	`removeConstraint(String identifier)` Removes from the model the constraints indicated by the given identifier
`void`	`resetTimer()` Resets the timers that track the amount of time involved in each part of the computation, to write the time report with the
`void`	`setInitialSolution(String decisionVariableName, double initialValue)` Sets the initial solution of the optimization algorithm solving the problem (can be used for setting the starting solution in IPOPT solver).
`void`	`setInitialSolution(String decisionVariableName, DoubleMatrixND initialValue)` Sets the initial solution of the optimization algorithm solving the problem (to be used by some solvers like IPOPT).
`void`	`setInputParameter(String name, Collection<? extends Number> values, String rowColumnVector)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, double value)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, double[][] values)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, double[] values, String rowColumnVector)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, DoubleMatrix1D values, String rowColumnVector)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, DoubleMatrix2D array)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, DoubleMatrixND array)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, int value)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, int[] values, String rowColumnVector)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setInputParameter(String name, String expression)` Sets the value of the (arrayed) input parameter identified by its name.
`void`	`setIsIntegerDecisionVariable(String decisionVariableName, boolean isInteger)` Sets the isInteger flag for the decision variables array identified by the given name
`void`	`setLowerBoundDecisionVariable(String decisionVariableName, double x_l)` Sets the lower bound limit of the indicated decision variable array
`void`	`setLowerBoundDecisionVariable(String decisionVariableName, DoubleMatrixND x_l)` Sets the lower bound limit of the indicated decision variable array
`Expression`	`setObjectiveFunction(String minMax, String expression)` Sets the objective function of the optimization problem, and its direction (maximice or minimice).
`void`	`setUpperBoundDecisionVariable(String decisionVariableName, DoubleMatrixND x_u)` Sets the upper bound limit of the indicated decision variable array
`boolean`	`solutionIsFeasible()` Returns true if the problem was solved, and the solution obtained is feasible.
`boolean`	`solutionIsOptimal()` Returns true if the problem was solved, and the solution obtained is optimal according to the solver.
`void`	`solve(String solverName, Object... paramValuePairs)` Calls the indicated solver to solve the optimization problem in its current state (e.g. current objective function and input parameters set).
`String`	`timeReport()` Return a printed report with the time spended in the different parts of the problem: defining the variables, objective, constraints and solving.
`String`	`toString()` Returns a formatted string with some information of the optimization problem

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - OptimizationProblem
```
public OptimizationProblem()
```
    Creates an optimization problem object
- Method Detail
  - getAcceptedSolverNames
```
public static List<String> getAcceptedSolverNames()
```
    Returns the list of the names of the installed solvers, in the form that is accepted as the solverName inpt parameter of solve method
    
    Returns:
    
    see above
  - about
```
public String about()
```
    Returns an informative string about the JOM library
    
    Returns:
    
    the string
  - removeConstraint
```
public boolean removeConstraint(String identifier)
```
    Removes from the model the constraints indicated by the given identifier
    
    Parameters:
    
    identifier - the identifier, as indicated in the addConstraint method
    
    Returns:
    
    true if the constraints existed, and thus were removed, false otherwise
  - hasConstraint
```
public boolean hasConstraint(String identifier)
```
    Indicates if a constraint set with the given identifier exists in the model
    
    Parameters:
    
    identifier - the identifier of the constraint to check
    
    Returns:
    
    see above
  - hasDecisionVariable
```
public boolean hasDecisionVariable(String identifier)
```
    Indicates if a decision variable with the given identifier exists in the model
    
    Parameters:
    
    identifier - the identifier of the constraint to check
    
    Returns:
    
    see above
  - addConstraint
```
public Expression addConstraint(String expression)
```
    Adds (an array of) constraints to the optimization problem. No identifier is assigned, so after the problem is solved, it is not possible to access the multipliers and other constraint-related info. Constraints have the form: expression-left-hand-side connector expression-right-hand-side. Expressions are strings that can be evaluated to arrayed expressions of the defined input parameters and decision variables. Connectors must be of the type less-equal (<= or =<), greater-equal (>= or =>) or equal (==).
    
    Parameters:
    
    expression - The string expression of the constraint.
    
    Returns:
    
    The Expression object holding the expression (lhs - rhs), where lhs and rhs are the expression in the left-hand-side and right-hand-side of the constraint
  - addConstraint
```
public Expression addConstraint(String expression,
                                String identifier)
```
    Adds (an array of) constraints to the optimization problem. Constraints have the form: expression-left-hand-side connector expression-right-hand-side. Expressions are strings that can be evaluated to arrayed expressions of the defined input parameters and decision variables. Connectors must be of the type less-equal (<= or =<), greater-equal (>= or =>) or equal (==).
    
    Parameters:
    
    expression - The string expression of the constraint.
    
    identifier - A unique string given to identify this constraint
    
    Returns:
    
    The Expression object holding the expression (lhs - rhs), where lhs and rhs are the expression in the left-hand-side and right-hand-side of the constraint
  - addDecisionVariable
```
public void addDecisionVariable(String name,
                                boolean isInteger,
                                int[] size)
```
    Same as addDecisionVariable(name, isInteger, size, null, null);
    
    Parameters:
    
    name - Name of the array of decision variables, as it will used in the expressions.
    
    isInteger - True if the decision variables in the array are all constrained to be integer
    
    size - One coordinate per dimension of the array, each coordinate is the size of the array in the respective dimension.
  - addDecisionVariable
```
public void addDecisionVariable(String name,
                                boolean isInteger,
                                int[] size,
                                double x_l,
                                double x_u)
```
    addDecisionVariable(String name, boolean isInteger, int[] size, DoubleMatrixND x_l, DoubleMatrixND x_u), but now the lower (upper) bounds for all the decision variables in the array are equal to x_l (x_u).
    
    Parameters:
    
    name - Name of the array of decision variables, as it will used in the expressions.
    
    isInteger - True if the decision variables in the array are all constrained to be integer
    
    size - One coordinate per dimension of the array, each coordinate is the size of the array in the respective dimension.
    
    x_l - The lower bounds of the variables are created as new DoubleMatrixND (size,x_l)
    
    x_u - The upper bounds of the variables are created as new DoubleMatrixND (size,x_u)
  - addDecisionVariable
```
public void addDecisionVariable(String name,
                                boolean isInteger,
                                int[] size,
                                double[] x_l,
                                double[] x_u)
```
    Adds an array of decision variables to the optimization problem
    
    Parameters:
    
    name - Name of the array of decision variables, as it will used in the expressions.
    
    isInteger - True if the decision variables in the array are all constrained to be integer
    
    size - One coordinate per dimension of the array, each coordinate is the size of the array in the respective dimension.
    
    x_l - The lower bounds of the variables are created as new DoubleMatrixND (size,x_l)
    
    x_u - The upper bounds of the variables are created as new DoubleMatrixND (size,x_u)
  - addDecisionVariable
```
public void addDecisionVariable(String name,
                                boolean isInteger,
                                int[] size,
                                DoubleMatrix1D x_l,
                                DoubleMatrix1D x_u)
```
    Adds an array of decision variables to the optimization problem
    
    Parameters:
    
    name - Name of the array of decision variables, as it will used in the expressions.
    
    isInteger - True if the decision variables in the array are all constrained to be integer
    
    size - One coordinate per dimension of the array, each coordinate is the size of the array in the respective dimension.
    
    x_l - The lower bounds of the variables are created as new DoubleMatrixND (size,x_l)
    
    x_u - The upper bounds of the variables are created as new DoubleMatrixND (size,x_u)
  - addDecisionVariable
```
public void addDecisionVariable(String name,
                                boolean isInteger,
                                int[] size,
                                DoubleMatrixND x_l,
                                DoubleMatrixND x_u)
```
    Adds an array of decision variables to the optimization problem
    
    Parameters:
    
    name - Name of the array of decision variables, as it will used in the expressions.
    
    isInteger - True if the decision variables in the array are all constrained to be integer
    
    size - One coordinate per dimension of the array, each coordinate is the size of the array in the respective dimension.
    
    x_l - An array of doubles of the same size of the decision variables, with the lower bounds of the variables.
    
    x_u - An array of doubles of the same size of the decision variables, with the upper bounds of the variables.
  - setIsIntegerDecisionVariable
```
public void setIsIntegerDecisionVariable(String decisionVariableName,
                                         boolean isInteger)
```
    Sets the isInteger flag for the decision variables array identified by the given name
    
    Parameters:
    
    decisionVariableName - the name, as introduced with addDecisionVariable
    
    isInteger - true if the variables are contrained to be integer
  - setLowerBoundDecisionVariable
```
public void setLowerBoundDecisionVariable(String decisionVariableName,
                                          DoubleMatrixND x_l)
```
    Sets the lower bound limit of the indicated decision variable array
    
    Parameters:
    
    decisionVariableName - the name, as introduced with addDecisionVariable
    
    x_l - an array with the same size as the decision variable, with the new bound
  - setLowerBoundDecisionVariable
```
public void setLowerBoundDecisionVariable(String decisionVariableName,
                                          double x_l)
```
    Sets the lower bound limit of the indicated decision variable array
    
    Parameters:
    
    decisionVariableName - the name, as introduced with addDecisionVariable
    
    x_l - a constant, the new bound
  - setUpperBoundDecisionVariable
```
public void setUpperBoundDecisionVariable(String decisionVariableName,
                                          DoubleMatrixND x_u)
```
    Sets the upper bound limit of the indicated decision variable array
    
    Parameters:
    
    decisionVariableName - the name, as introduced with addDecisionVariable
    
    x_u - an array with the same size as the decision variable, with the new bound
  - feasibleSolutionDoesNotExist
```
public boolean feasibleSolutionDoesNotExist()
```
    Returns true if the problem was attempted to be solved, and the solver declares that the problem has no feasible solutions. If the method "solve" was not invoked yet, throws an exception
    
    Returns:
    
    See above
  - foundUnboundedSolution
```
public boolean foundUnboundedSolution()
```
    Returns true if the problem was attempted to be solved, and the solver declares that the problem is unbounded. If the method "solve" was not invoked yet, throws an exception
    
    Returns:
    
    See above
  - getInputParameter
```
public DoubleMatrixND getInputParameter(String name)
```
    Obtains the value (an array of doubles) of the input parameter previously set
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions
    
    Returns:
    
    The value of the input parameter
  - getMultiplierOfLowerBoundConstraintToPrimalVariables
```
public DoubleMatrixND getMultiplierOfLowerBoundConstraintToPrimalVariables(String decisionVariableName)
```
    Returns the multipliers of the automatic constraints: \(x_l \leq varName\) added to the problem, where \(x_l\) is the array of lower bounds provided, associated to the decision variable.
    
    Parameters:
    
    decisionVariableName - The name of the decision variable
    
    Returns:
    
    The multipliers as an array of the same size of the decision variables
  - getMultiplierOfUpperBoundConstraintToPrimalVariables
```
public DoubleMatrixND getMultiplierOfUpperBoundConstraintToPrimalVariables(String decisionVariableName)
```
    Returns the multipliers of the automatic constraints: \(varName \leq x_u\) added to the problem, where \(x_u\) is the array of upper bounds provided, associated to the decision variable.
    
    Parameters:
    
    decisionVariableName - The name of the decision variable
    
    Returns:
    
    The multipliers as an array of the same size of the decision variables
  - getMultipliersOfConstraint
```
public DoubleMatrixND getMultipliersOfConstraint(String constraintIdentifier)
```
    Returns the multipliers of the given constraint
    
    Parameters:
    
    constraintIdentifier - The unique identifier of the constraint
    
    Returns:
    
    The multipliers as an array of the same size of the constraints
  - getNumLinearScalarConstraints
```
public int getNumLinearScalarConstraints()
```
    Gets the number of scalar constraints in the problem that are linear (with integer variables or not). Arrayed constraints are counted as many times as its number of constituting scalar elements.
    
    Returns:
    
    The number of linear scalar constraints
  - getNumNonLinearScalarConstraints
```
public int getNumNonLinearScalarConstraints()
```
    Gets the number of scalar constraints in the problem that are non linear (with integer variables or not). Arrayed constraints are counted as many times as its number of constituting scalar elements.
    
    Returns:
    
    The number of non-linear scalar constraints
  - getNumScalarDecisionVariables
```
public int getNumScalarDecisionVariables()
```
    Gets the number of scalar decision variables. Arrayed decision variables are counted as many times as its number of constituting scalar elements.
    
    Returns:
    
    The number of scalar decision variables
  - getObjectiveFunction
```
public Expression getObjectiveFunction()
```
    Gets the objective function expression set in the problem
    
    Returns:
    
    The objective expression of the objective function
  - getOptimalCost
```
public double getOptimalCost()
```
    Returns the cost of the solution obtained by the solver
    
    Returns:
    
    The primal solution cost
  - getBestOptimalityBound
```
public double getBestOptimalityBound()
```
    Returns the best optimality bound found by the solver. This is a lower bound of the value of an optimum solution in minimization problems, and an upper bound in maximization problems. Some solvers are able to provide this information, even if a feasible solution is not found. If this information is not available, -Double.MAX_VALUE is returned in minimization problems, and Double.MAX_VALUE is returned in maximization problems.
    
    Returns:
    
    The optimality bound
  - getPrimalSolution
```
public DoubleMatrixND getPrimalSolution(String decisionVariable)
```
    Returns the primal solution obtained after solving the problem for the given (array of) decision variables. If the decision variable is constrained to be integer, it is rounded. In this case, we are assuming that non-integer values returned by the solver were caused by negligible numerical errors. Recall that, after the solver ends, JOM checks if its exit code signals an error-free execution. Thus, if the solver returns an "everything ok" code, numerical errors in integer variables should be negligible.
    
    Parameters:
    
    decisionVariable - The name of the decision variable
    
    Returns:
    
    An array of the same size of the decision variables, with the solution
  - getSlackOfConstraint
```
public DoubleMatrixND getSlackOfConstraint(String constraintIdentifier)
```
    Returns the slack of the given constraints. It should be zero for equality constraints.
    
    Parameters:
    
    constraintIdentifier - Id of the constrain
    
    Returns:
    
    An array of the same size of the constraints, with the slack values
  - isInputParameter
```
public boolean isInputParameter(String name)
```
    Returns true if the given name corresponds to an input parameter defined for the problem
    
    Parameters:
    
    name - Name of the input parameter
    
    Returns:
    
    True if the previous statement is true, false otherwise
  - isIntegerProblem
```
public boolean isIntegerProblem()
```
    Returns true if the problem has one or more decision variables constrained to be integer, false otherwise
    
    Returns:
    
    See above.
  - isLinearProblem
```
public boolean isLinearProblem()
```
    Returns true if the problem is linear (with some/all integer variables or not). False if the objective function or one or more constraints are non-linear.
    
    Returns:
    
    See above
  - isToMinimize
```
public boolean isToMinimize()
```
    Returns true if the current objective function has already been defined, and the problem is set as a minimization problem
    
    Returns:
    
    True if the previous statement is true, false otherwise
  - parseExpression
```
public Expression parseExpression(String expression)
```
    Help function (not needed usually for solving optimization problems) to generate an Expression object from its String representation.
    
    Parameters:
    
    expression - The string expression.
    
    Returns:
    
    The Expression object
  - resetTimer
```
public void resetTimer()
```
    Resets the timers that track the amount of time involved in each part of the computation, to write the time report with the
  - setInitialSolution
```
public void setInitialSolution(String decisionVariableName,
                               double initialValue)
```
    Sets the initial solution of the optimization algorithm solving the problem (can be used for setting the starting solution in IPOPT solver).
    
    Parameters:
    
    decisionVariableName - Name of the decision variable
    
    initialValue - Initial solution. All the scalar decision variables in the array of decision variables have this same initial value.
  - setInitialSolution
```
public void setInitialSolution(String decisionVariableName,
                               DoubleMatrixND initialValue)
```
    Sets the initial solution of the optimization algorithm solving the problem (to be used by some solvers like IPOPT).
    
    Parameters:
    
    decisionVariableName - Name of the decision variable
    
    initialValue - Initial solution. Array of the same size as the decision variable
  - setInputParameter
```
public void setInputParameter(String name,
                              double value)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    value - The scalar value of the input parameter, converted to an N-DIM array object of size (1,1)
  - setInputParameter
```
public void setInputParameter(String name,
                              double[] values,
                              String rowColumnVector)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    values - The 1D array of values of the input parameter, converted to an N-DIM array object of size (1,values.length)
    
    rowColumnVector - "row" for a row vector, "column" for a column vector
  - setInputParameter
```
public void setInputParameter(String name,
                              DoubleMatrix1D values,
                              String rowColumnVector)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    values - The 1D array of values of the input parameter, converted to an N-DIM array object of size (1,values.length)
    
    rowColumnVector - "row" for a row vector, "column" for a column vector
  - setInputParameter
```
public void setInputParameter(String name,
                              Collection<? extends Number> values,
                              String rowColumnVector)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    values - A collection with values of type Number (e.g. Double, Integer, Long...) of the input parameter
    
    rowColumnVector - "row" for a row vector, "column" for a column vector
  - setInputParameter
```
public void setInputParameter(String name,
                              double[][] values)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    values - The 2D array of values of the input parameter, converted to an N-DIM array object of the same size
  - setInputParameter
```
public void setInputParameter(String name,
                              DoubleMatrixND array)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    array - The array of values of the input parameter
  - setInputParameter
```
public void setInputParameter(String name,
                              DoubleMatrix2D array)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    array - The array of values of the input parameter
  - setInputParameter
```
public void setInputParameter(String name,
                              int value)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    value - The scalar value of the input parameter, casted to double, and converted to an N-DIM array object of size (1,1)
  - setInputParameter
```
public void setInputParameter(String name,
                              int[] values,
                              String rowColumnVector)
```
    Sets the value of the (arrayed) input parameter identified by its name. If an input parameter with the same name was previously set, the old values are lost
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    values - The 1D array of values of the input parameter, casted to double, and converted to an N-DIM array object of size (1,values .length)
    
    rowColumnVector - "row" for a row vector, "column" for a column vector
  - setInputParameter
```
public void setInputParameter(String name,
                              String expression)
```
    Sets the value of the (arrayed) input parameter identified by its name. The String should be evaluated to a constant Expression.
    
    Parameters:
    
    name - Name of the input parameter as it appears in the expressions.
    
    expression - array The expression is evaluated using a common parseExpression. If it is not constant, an Exception is raised.
  - setObjectiveFunction
```
public Expression setObjectiveFunction(String minMax,
                                       String expression)
```
    Sets the objective function of the optimization problem, and its direction (maximice or minimice). If an objective function and direction was previously set, they are lost.
    
    Parameters:
    
    minMax - "Minimize" if the target is to minimize this expression, "Maximize" if the target is to maximize this expression
    
    expression - The string expression of the objective function, that should successfully parsed as an scalar expression of the decision variables and input parameters of the problem
    
    Returns:
    
    The Expression object associated to the objective function
  - solutionIsFeasible
```
public boolean solutionIsFeasible()
```
    Returns true if the problem was solved, and the solution obtained is feasible. If the method "solve" was not invoked yet, throws an exception
    
    Returns:
    
    See above
  - solutionIsOptimal
```
public boolean solutionIsOptimal()
```
    Returns true if the problem was solved, and the solution obtained is optimal according to the solver. If the method "solve" was not invoked yet, throws an exception
    
    Returns:
    
    See above
  - solve
```
public void solve(String solverName,
                  Object... paramValuePairs)
```
    Calls the indicated solver to solve the optimization problem in its current state (e.g. current objective function and input parameters set).
    
    Parameters:
    
    solverName - The name of the solver to be used. Current supported solvers are GLPK (solverName "glpk") and CPLEX (solverName "cplex") for mixed integer linear problems and IPOPT (solverName "ipopt") for non-linear non-integer problems.
    
    paramValuePairs - Parameters to be passed to the solver to tune its operation. An even number of Object objects is to be passed. For each object pair, first Object must be a String with the name of the parameter, second a general Object with its value. If no name-value pairs are set, solver default values are used. For the "solverLibraryName" parameter, passing a value equal to an empty string "" is equivalent to not passing this parameter. See the documentation for further information.
  - timeReport
```
public String timeReport()
```
    Return a printed report with the time spended in the different parts of the problem: defining the variables, objective, constraints and solving.
    
    Returns:
    
    a formatted string with the report
  - toString
```
public String toString()
```
    Returns a formatted string with some information of the optimization problem
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    The string

Class OptimizationProblem

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

OptimizationProblem

Method Detail

getAcceptedSolverNames

about

removeConstraint

hasConstraint

hasDecisionVariable

addConstraint

addConstraint

addDecisionVariable

addDecisionVariable

addDecisionVariable

addDecisionVariable

addDecisionVariable

setIsIntegerDecisionVariable

setLowerBoundDecisionVariable

setLowerBoundDecisionVariable

setUpperBoundDecisionVariable

feasibleSolutionDoesNotExist

foundUnboundedSolution

getInputParameter

getMultiplierOfLowerBoundConstraintToPrimalVariables

getMultiplierOfUpperBoundConstraintToPrimalVariables

getMultipliersOfConstraint

getNumLinearScalarConstraints

getNumNonLinearScalarConstraints

getNumScalarDecisionVariables

getObjectiveFunction

getOptimalCost

getBestOptimalityBound

getPrimalSolution

getSlackOfConstraint

isInputParameter

isIntegerProblem

isLinearProblem

isToMinimize

parseExpression

resetTimer

setInitialSolution

setInitialSolution

setInputParameter

setInputParameter

setInputParameter

setInputParameter

setInputParameter

setInputParameter

setInputParameter

setInputParameter

setInputParameter

setInputParameter

setObjectiveFunction

solutionIsFeasible

solutionIsOptimal

solve

timeReport

toString