Switch

A switch statement compares a “switch” value to several alternate “case” values. If the switch value matches one of these case values, the associated statements will be executed. A switch or a case value should be a scalar or an array of characters.

For motivation, consider the following example. The switch statement here determines my phone's brand: Apple, Samsung, Nokia, or an unknown brand.

The value of myphone is compared to the case values one by one:

• It starts from the first, which is 'apple'.
• If it does not match 'apple', it compares with the next, which is 'samsung'.
• If it does not match 'samsung', it tries 'nokia'.
• If eventually none of the given case values is matched, statements under otherwise will be executed.

Input

myphone='apple';
switch myphone
    case 'apple'
        disp('It is an Apple phone')
    case 'samsung'
        disp('It is a Samsung phone')
    case 'nokia'
        disp('It is a nokia phone')
    otherwise
        disp('It is an unknown brand')
end

Output

It is an Apple phone

Note that otherwise is not mandatory. You can omit otherwise if there is nothing to execute when the variable matches none of the case values.

Syntax

The switch statement has the following syntax pattern:

switch expression
	case expression_1
		statements
	case expression_2
		statements
	...
	case expression_n
		statements
	otherwise
		statements
end

• Each of expression and expression_1, expression_2, ..., expression_n should evaluate to a character array or a scalar.
• If expression and expression_i evaluate to the same values, then the statements under expression_i will be executed.
• If no matching case is found, statements below otherwise are executed. But, otherwise is not mandatory and can be skipped.

Difference with MATLAB