MATLAB Programming

Warning Control
Example 2 — Performing an Implicit Query
Turn on one particular warning, saving the previous state of this warning
in s. Remember that this nonquery syntax (where state equals on or off)
performs an implicit query prior to setting the new state.
s = warning('on', 'Control:parameterNotSymmetric');
Restore the state of that one warning when you are ready, with
warning(s)
BacktraceandVerboseModes
In addition to warning messages, there are two modes that can be enabled or
disabled with a warning control statement. These modes are shown here.
Mode Description Default
backtrace
verbose
Display an M-stack trace
after a warning is invoked.
Display a message on how to
suppress the warning.
on (enabled)
off (terse)
The syntax for using this type of control statement is as follows, where state,
in this case, can be only on, off, orquery.
warning state mode
Notethatthereisnoneedtoincludeamessage identifier with this type of
control statement. All enabled warnings are affected by the this type of
control statement.
Example 1 — Displaying a Stack Trace on a Specific Warning
It can be difficult to locate the source of a warning when it is generated
from code buried in several levels of function calls. This example generates
a warning within a function that is nested several levels deep within the
primary function in file f1.m:
function f1(a, b)
for k = a:-1:b
f2(k)
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