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Subsections

ERROR Causes an Error Condition Raised

Usage

The error function causes an error condition (exception to be raised). The general syntax for its use is

   error(s),

where s is the string message describing the error. The error function is usually used in conjunction with try and catch to provide error handling.

Example

Here is a simple example of an error being issued by a function evenoddtest:

 evenoddtest.m
function evenoddtest(n)
  if (n==0)
    error('zero is neither even nor odd');
  elseif (typeof(n) ~= 'int32')
    error('expecting integer argument');
  end;
  if (n==int32(n/2)*2)
    printf('%d is even\n',n);
  else
    printf('%d is odd\n',n);
  end

The normal command line prompt --> simply prints the error that occured.

--> evenoddtest(4)
4 is even
--> evenoddtest(5)
5 is odd
--> evenoddtest(0)
Error: zero is neither even nor odd
   at built-in function error
--> evenoddtest(pi)
Error: Size mismatch on arguments to arithmetic operator.
   at built-in binary operator



2004-10-27