Conditional Statements
Conditional statements enable you to select at run time which block of code to execute. The simplest
conditional statement is an if statement. For example:
% Generate a random number
a = randi(100, 1);
% If it is even, divide by 2
if rem(a, 2) == 0
disp('a is even')
b = a/2;
end
if statements can include alternate choices, using the optional keywords elseif or else. For
example:
a = randi(100, 1);
if a < 30
disp('small')
elseif a < 80
disp('medium')
else
disp('large')
end
Alternatively, when you want to test for equality against a set of known values, use a switch
statement. For example:
[dayNum, dayString] = weekday(date, 'long', 'en_US');
switch dayString
case 'Monday'
disp('Start of the work week')
case 'Tuesday'
disp('Day 2')
case 'Wednesday'
disp('Day 3')
case 'Thursday'
disp('Day 4')
case 'Friday'
disp('Last day of the work week')
otherwise
disp('Weekend!')
end
For both if and switch, MATLAB executes the code corresponding to the first true condition, and
then exits the code block. Each conditional statement requires the end keyword.
In general, when you have many possible discrete, known values, switch statements are easier to
read than if statements. However, you cannot test for inequality between switch and case values.
For example, you cannot implement this type of condition with a switch:
yourNumber = input('Enter a number: ');
if yourNumber < 0
Conditional Statements
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