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FreeMat
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Section: Flow Control
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. If the string s, then (to conform to the MATLAB API), error does nothing.
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 ( n ~= fix(n) )
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)
In /home/sbasu/Devel/FreeMat4/doc/fragments/evenoddtest.m(evenoddtest) at line 3
In scratch() at line 1
In base(base)
In base()
In global()
Error: zero is neither even nor odd
--> evenoddtest(pi)
In /home/sbasu/Devel/FreeMat4/doc/fragments/evenoddtest.m(evenoddtest) at line 5
In scratch() at line 1
In base(base)
In base()
In global()
Error: expecting integer argument