MATLAB Programming

Program Control
through; only one case may execute. Using break within a case statement is
not only unnecessary, it is also invalid and generates a warning.
In this example, if result is 52, onlythefirstdisp statement executes, even
though the second is also a valid match:
switch(result)
case 52
disp('result is 52')
case {52, 78}
disp('result is 52 or 78')
end
Variable Scope in a switch
Since MATLAB executes only one case of any switch statement, variables
defined within one case arenotknownintheothercases of that switch
statement. The same holds true for if-elseif statements.
In these examples, you get an error when choice equals 2, becausex is
undefined.
-- SWITCH-CASE -- -- IF-ELSEIF --
switch choice
case 1 if choice == 1
x = -pi:0.01:pi;
x = -pi:0.01:pi;
case 2 elseif choice == 2
plot(x, sin(x));
plot(x, sin(x));
end
end
Catching Errors with try-catch
When you have statements in your code that could possibly generate
unwanted results, put those statements into a try-catch block that will catch
any errors and handle them appropriately.
The example below shows a try-catch block within a function that multiplies
two matrices. If a statement in the try segment of the block fails, control
passes to the catch segment. In this case, the catch statements check
the error message that was issued (returned by lasterr) andrespond
appropriately.
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