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To use the genetic algorithm at the command line, call the genetic
algorithm function `ga` with the syntax

[x fval] = ga(@fitnessfun, nvars, options)

where

`@fitnessfun`is a handle to the fitness function.`nvars`is the number of independent variables for the fitness function.`options`is a structure containing options for the genetic algorithm. If you do not pass in this argument,`ga`uses its default options.

The results are given by

`x`— Point at which the final value is attained`fval`— Final value of the fitness function

For an example, see Finding the Minimum from the Command Line.

Using the function `ga` is convenient if
you want to

Return results directly to the MATLAB

^{®}workspaceRun the genetic algorithm multiple times with different options, by calling

`ga`from a file

To open the Optimization app, enter

optimtool('ga')

at
the command line, or enter `optimtool` and then choose `ga` from
the **Solver** menu.

You can also start the tool from the MATLAB **Apps** tab.

To use the Optimization app, you must first enter the following information:

**Fitness function**— The objective function you want to minimize. Enter the fitness function in the form`@fitnessfun`, where`fitnessfun.m`is a file that computes the fitness function. Compute Objective Functions explains how write this file. The`@`sign creates a function handle to`fitnessfun`.**Number of variables**— The length of the input vector to the fitness function. For the function`my_fun`described in Compute Objective Functions, you would enter`2`.

You can enter constraints or a nonlinear constraint function
for the problem in the **Constraints** pane.
If the problem is unconstrained, leave these fields blank.

To run the genetic algorithm, click the **Start** button.
The tool displays the results of the optimization in the **Run
solver and view results** pane.

You can change the options for the genetic algorithm in the **Options** pane.
To view the options in one of the categories listed in the pane, click
the + sign next to it.

For more information,

See Optimization App in the Optimization Toolbox™ documentation.

See Minimize Rastrigin's Function for an example of using the tool.

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