MATLAB Programming

3 Basic Program Components
ans =
g11n
Using a dynamic expression ${num2str(length($2))} enables you to base
the replacement expression on the input string so that you do not have to
change the expression each time. This example uses the dynamic syntax
${cmd} from the second table shown above:
match_expr = '(^\w)(\w*)(\w$)';
replace_expr = '$1${num2str(length($2))}$3';
regexprep('internationalization', match_expr, replace_expr)
ans =
i18n
regexprep('globalization', match_expr, replace_expr)
ans =
g11n
Dynamic Operators for the Match Expression
There are three types of dynamic expressions you can use when composing a
match expression:
• “Dynamic Expressions that Modify the Match Expression — (??expr)” on
page 3-61
“Dynamic Commands that Modify the Match Expression — (??@cmd)” on
page 3-61
“Dynamic Commands that Serve a Functional Purpose — (?@cmd)” on
page 3-62
The first two of these actually modify the match expression itself so that it can
be made specific to changes in the contents of the input string. When MATLAB
evaluates one of these dynamic statements, the results of that evaluation are
included in the same location within the overall match expression.
The third operator listed here does not modify the overall expression, but
instead enables you to run MATLAB commands during the parsing of a
regular expression. This functionality can be useful in diagnosing your
regular expressions.
3-60