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Although the Optimization app affords convenient ways to set options and run problems, it will be removed in a future release. This topic describes other ways to accomplish optimization tasks without using the app.

Set options easily — Set Options Using Live Scripts or Set Options: Command Line or Standard Scripts

Monitor the optimization — Choose Plot Functions

Pass solver arguments correctly — Pass Solver Arguments

Beginning with R2018a, live scripts show suggestions for
`optimoptions`

names and values.

On the

**Home**tab, in the**File**section, click**New Live Script**to create a live script.In the Live Editor, set options by entering

`options = optimoptions(`

. MATLAB^{®}shows a list of solvers.Select a solver, then enter a comma. MATLAB displays a list of name-value pairs for the solver.

Select a name-value pair in one of these ways:

Click the name-value pair.

Use the arrow keys to highlight the name-value pair, and then press

**Tab**.Type the first letters of the name-value pair, and then press

**Tab**.

Enter the appropriate value for the selected name. If the value is from a list of choices, you can select it the same way that you selected the name.

Continue adding name-value pairs until the options are complete.

Be sure to pass the options to your solver.

[x,fval,exitflag,output] = ... fmincon(fun,x0,A,b,Aeq,beq,lb,ub,nlcon,

**options**)

For help choosing a solver, see Optimization Decision Table.

For help choosing the solver algorithm, see Choosing the Algorithm.

To understand the meaning of other options, see Set Options.

Beginning with R2018a, the MATLAB command line and the standard Editor show suggestions for
`optimoptions`

names and values.

Set options by entering

`options = optimoptions('`

and pressing**Tab**. MATLAB shows a list of solvers.Select a solver in one of these ways:

Double-click the solver.

Use the arrow keys to highlight the solver, and then press

**Tab**.Type the first letters of the solver, and then press

**Tab**.

Enter

`','`

and then press**Tab**. MATLAB displays a list of name-value pairs for the solver.Select a name-value pair using one of the ways described in step 2.

Enter the appropriate value for the selected name. If the value is from a list of choices, you can select it the same way that you selected the name.

Continue adding name-value pairs until the options are complete.

Be sure to pass the options to your solver.

[x,fval,exitflag,output] = ... fmincon(fun,x0,A,b,Aeq,beq,lb,ub,nlcon,

**options**)

For help choosing a solver, see Optimization Decision Table.

For help choosing the solver algorithm, see Choosing the Algorithm.

To understand the meaning of other options, see Set Options.

To monitor your optimization while it runs, use a plot function. Solvers have a
set of built-in plot functions. Use `optimoptions`

to set the
`'PlotFcn'`

name-value pair to a built-in plot function, a cell
array of built-in plot functions, or a function handle or cell array of function
handles to plot functions.

Choose plot functions using live scripts:

To choose plot functions using the Editor or the command line, enter ```
options =
optimoptions('
```

and
then press * solvername*','PlotFcn',{'

To choose a custom plot function, pass a function handle such as
`@myplotfun`

. For details on writing a custom plot function,
see Plot Function Syntax.

`linprog`

, `lsqlin`

,
`quadprog`

, and `lsqnonneg`

do not support
plot functions, because these solvers typically run quickly. To monitor their
progress, you can use iterative display for `linprog`

, the
`lsqlin`

`'interior-point'`

algorithm, and the `quadprog`

`'interior-point-convex'`

algorithm. Set the
`'Display'`

option to `'iter'`

.

The `fminbnd`

, `fminsearch`

, and
`fzero`

solvers do not use options created by
`optimoptions`

, only `optimset`

. To see
which plot functions these solvers use, consult their reference pages:

Solvers use positional function arguments. For example, the syntax for
`fmincon`

arguments is

fmincon(fun,x0,A,b,Aeq,beq,lb,ub,nonlcon,options)

If you want to include only `fun`

, `x0`

,
`lb`

, and `options`

arguments, then the
appropriate syntax is

fmincon(fun,x0,[],[],[],[],lb,[],[],options)

Sometimes the inexperienced will, instead, write

`fmincon(fun,x0,lb,options) % This is incorrect!`

This call throws an error. In this incorrect command, `fmincon`

interprets the `lb`

argument as representing the
`A`

matrix, and the `options`

argument as
representing the `b`

vector. The third argument always represents
the `A`

matrix, and the fourth argument always represents the
`b`

vector.

It can be difficult to keep track of positional arguments as you enter a command. The following are suggestions for obtaining the correct syntax.

Use live scripts. As you enter a command, you see function hints that guide you to enter the correct argument in each position. Enter

`[]`

for unused arguments.Use the MATLAB Editor or command line. As you enter commands, you see lists of proper syntax that guide you to enter the correct argument in each position. Enter

`[]`

for unused arguments.Create a

`problem`

structure. This way, you can pass fewer arguments and pass named arguments instead of positional arguments. For`fmincon`

, the`problem`

structure requires at least the`objective`

,`x0`

,`solver`

, and`options`

fields. So, to give only the`fun`

,`x0`

,`lb`

, and`options`

arguments, create a`problem`

structure as follows:% These commands assume that fun, x0, lb, and opts exist prob.objective = fun; prob.x0 = x0; prob.lb = lb; prob.options = opts; prob.solver = 'fmincon';

You can also create a

`problem`

structure using one`struct`

command.% This command assumes that fun, x0, lb, and opts exist prob = struct('objective',fun,'x0',x0,'lb',lb,... 'options',opts,'solver','fmincon')

If you have Global Optimization Toolbox, you can create a problem structure for

`fmincon`

,`fminunc`

,`lsqcurvefit`

, and`lsqnonlin`

by using`createOptimProblem`

.