show

Display information about optimization object

Syntax

show(obj)

Description

Use show to display information about an optimization object.

Tip

For the full workflow, see Problem-Based Optimization Workflow or Problem-Based Workflow for Solving Equations.

show(obj) displays information about obj at the command line. If the object display is large, consider using write instead to save the information in a text file.

Examples

Examine Problem-Based Setup

Examine the various stages of problem construction for optimizing the Rosenbrock function confined to the unit disk (see Solve a Constrained Nonlinear Problem, Problem-Based).

Create a 2-D optimization variable x. Show the variable.

x = optimvar('x',2);
show(x)

    [ x(1) ]
    [ x(2) ]

Create an expression for the objective function. Show the expression.

obj = 100*(x(2) - x(1)^2)^2 + (1 - x(1))^2;
show(obj)

  ((100 .* (x(2) - x(1).^2).^2) + (1 - x(1)).^2)

Create an expression for the constraint. Show the constraint.

cons = x(1)^2 + x(2)^2 <= 1;
show(cons)

  (x(1).^2 + x(2).^2) <= 1

Create an optimization problem that has obj as the objective function and cons as the constraint. Show the problem.

prob = optimproblem("Objective",obj,"Constraints",cons);
show(prob)

  OptimizationProblem : 

	Solve for:
       x

	minimize :
       ((100 .* (x(2) - x(1).^2).^2) + (1 - x(1)).^2)


	subject to :
       (x(1).^2 + x(2).^2) <= 1
     

Finally, create an initial point [0 0] and solve the problem starting at the initial point.

x0.x = [0 0];
[sol,fval,exitflag] = solve(prob,x0)

Solving problem using fmincon.

Local minimum found that satisfies the constraints.

Optimization completed because the objective function is non-decreasing in 
feasible directions, to within the value of the optimality tolerance,
and constraints are satisfied to within the value of the constraint tolerance.

sol = struct with fields:
    x: [2x1 double]

fval = 0.0457

exitflag = 
    OptimalSolution

Examine the solution point.

sol.x

ans = 2×1

    0.7864
    0.6177

Input Arguments

obj — Optimization object

OptimizationProblem object | EquationProblem object | OptimizationExpression object | OptimizationVariable object | OptimizationConstraint object | OptimizationEquality object | OptimizationInequality object

Optimization object, specified as one of the following:

• OptimizationProblem object — show(obj) displays the variables for the solution, objective function, constraints, and variable bounds.

• EquationProblem object — show(obj) displays the variables for the solution, equations for the solution, and variable bounds.

• OptimizationExpression object — show(obj) displays the optimization expression.

• OptimizationVariable object — show(obj) displays the optimization variables. This display does not indicate variable types or bounds; it shows only the variable dimensions and index names (if any).

• OptimizationConstraint object — show(obj) displays the constraint expression.

• OptimizationEquality object — show(obj) displays the equality expression.

• OptimizationInequality object — show(obj) displays the inequality expression.

Version History

Introduced in R2019b