MATLAB Programming

8 Error Handling
Checking for Errors with try-catch
No matter how carefully you plan and test the programs you write, they may
not always run as smoothly as expected when run under different conditions.
It is always a good idea to include error checking in programs to ensure
reliable operation under all conditions.
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 sample function that multiplies two matrices:
function matrixMultiply(A, B)
try
X = A * B
catch
disp '** Error multiplying A * B'
end
A try-catch block is divided into two sections. The first begins with try and
the second with catch. Terminate the block with end.
• All statements in the try segment are executed normally, just as if they
were in the regular code flow. But if any of these operations results in
an error, MATLAB skips the remaining statements in the try and jumps
to the catch segment of the block.
• The catch segment handles the error. In this example, it displays a general
error message. If there are different types of errors that can occur, you will
want to identify which error has been caught and respond to that specific
error. You can also try to recover from an error in the catch section.
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