MATLAB Programming

8 Error Handling
You must type the command using the MATLAB function format; that is,
parentheses and quotation marks are required.
Note MATLAB does not display warning output if you do not assign the
output to a variable.
This example turns off divideByZero warnings for the MATLAB component,
and returns the identifier and previous state in a 1-by-1 structure array.
s = warning('off','MATLAB:divideByZero')
s =
identifier: 'MATLAB:divideByZero'
state: 'on'
You can use output variables with any type of warning control statement. If
you just want to collect the information but don’t want to change state, then
simply perform a query on the warning(s). MATLAB returns the current state
of those warnings selected by the message identifier.
s = warning('query', 'msg_id');
Ifyouwanttochangestate,butalsosave the former state so that you can
restoreitlater,usethereturnstructurearraytosavethatstate.Thefollowing
example does an implicit query, returning state information in s, andthen
turns on all warnings.
s = warning('on', 'all');
See the section, “Saving and Restoring State” on page 8-22, for more
information on restoring the former state of warnings.
Output Structure Array
Each element of the structure array returned by warning contains two fields.
8-20